Speedup URL retrieval

EonaCat.DnsTester/EonaCat.DnsTester.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
-    <TargetFramework>net6.0-windows</TargetFramework>
+    <TargetFramework>net7.0-windows</TargetFramework>
     <UseWindowsForms>true</UseWindowsForms>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
 
@@ -28,5 +28,8 @@
       <Generator>SettingsSingleFileGenerator</Generator>
       <LastGenOutput>Settings.Designer.cs</LastGenOutput>
     </None>
+    <None Update="Servers.xml">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
   </ItemGroup>
 </Project>

EonaCat.DnsTester/Helpers/DnsHelper.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.Net;
 using System.Net.Sockets;
-using System.Reflection;
 using System.Text;
 using System.Threading.Tasks;
 
@@ -11,7 +10,7 @@ namespace EonaCat.DnsTester.Helpers
     class DnsHelper
     {
         public static event EventHandler<string> OnLog;
-        public static async Task<DnsResponse> SendDnsQueryPacket(string dnsId, string server, int port, byte[] queryBytes)
+        public static async Task<DnsResponse> SendDnsQueryPacketAsync(string dnsId, string server, int port, byte[] queryBytes)
         {
             // Start the clock
             var startTime = DateTime.Now.Ticks;
@@ -21,6 +20,7 @@ namespace EonaCat.DnsTester.Helpers
             {
                 client.DontFragment = true;
                 client.EnableBroadcast = false;
+                client.Client.SendTimeout = DnsSendTimeout;
                 client.Client.ReceiveTimeout = DnsReceiveTimeout;
                 byte[] responseBytes = null;
                 if (FakeResponse)
@@ -29,12 +29,12 @@ namespace EonaCat.DnsTester.Helpers
                 }
                 else
                 {
-                    await client.SendAsync(queryBytes, queryBytes.Length, endPoint);
+                    await client.SendAsync(queryBytes, queryBytes.Length, endPoint).ConfigureAwait(false);
-                    var responseResult = await client.ReceiveAsync();
+                    var responseResult = await client.ReceiveAsync().ConfigureAwait(false);
                     responseBytes = responseResult.Buffer;
                 }
 
-                DnsResponse response = ParseDnsResponsePacket(dnsId, startTime, server, responseBytes);
+                var response = ParseDnsResponsePacket(dnsId, startTime, server, responseBytes);
                 return response;
             }
         }
@@ -42,21 +42,22 @@ namespace EonaCat.DnsTester.Helpers
         // For testing purposes
         public static bool FakeResponse { get; set; }
 
+        public static int DnsSendTimeout { get; set; } = 5;
         public static int DnsReceiveTimeout { get; set; } = 5;
 
 
         public static byte[] CreateDnsQueryPacket(string domainName, DnsRecordType recordType)
         {
-            Random random = new Random();
+            var random = new Random();
 
             // DNS header
-            ushort id = (ushort)random.Next(0, 65536);
+            var id = (ushort)random.Next(0, 65536);
-            ushort flags = (ushort)0x0100; // recursion desired
+            var flags = (ushort)0x0100; // recursion desired
             ushort qdcount = 1;
             ushort ancount = 0;
             ushort nscount = 0;
             ushort arcount = 0;
-            byte[] headerBytes = new byte[]
+            var headerBytes = new byte[]
             {
                 (byte)(id >> 8), (byte)(id & 0xff),
                 (byte)(flags >> 8), (byte)(flags & 0xff),
@@ -67,28 +68,28 @@ namespace EonaCat.DnsTester.Helpers
             };
 
             // DNS question
-            string[] labels = domainName.Split('.');
+            var labels = domainName.Split('.');
-            byte[] qnameBytes = new byte[domainName.Length + 2];
+            var qnameBytes = new byte[domainName.Length + 2];
-            int qnameIndex = 0;
+            var qnameIndex = 0;
-            foreach (string label in labels)
+            foreach (var label in labels)
             {
                 qnameBytes[qnameIndex++] = (byte)label.Length;
-                foreach (char c in label)
+                foreach (var c in label)
                 {
                     qnameBytes[qnameIndex++] = (byte)c;
                 }
             }
             qnameBytes[qnameIndex++] = 0;
 
-            byte[] qtypeBytes = new byte[] { (byte)((ushort)recordType >> 8), (byte)((ushort)recordType & 0xff) };
+            var qtypeBytes = new byte[] { (byte)((ushort)recordType >> 8), (byte)((ushort)recordType & 0xff) };
-            byte[] qclassBytes = new byte[] { 0, 1 }; // internet class
+            var qclassBytes = new byte[] { 0, 1 }; // internet class
-            byte[] questionBytes = new byte[qnameBytes.Length + qtypeBytes.Length + qclassBytes.Length];
+            var questionBytes = new byte[qnameBytes.Length + qtypeBytes.Length + qclassBytes.Length];
             qnameBytes.CopyTo(questionBytes, 0);
             qtypeBytes.CopyTo(questionBytes, qnameBytes.Length);
             qclassBytes.CopyTo(questionBytes, qnameBytes.Length + qtypeBytes.Length);
 
             // Combine the header and question to form the DNS query packet
-            byte[] queryBytes = new byte[headerBytes.Length + questionBytes.Length];
+            var queryBytes = new byte[headerBytes.Length + questionBytes.Length];
             headerBytes.CopyTo(queryBytes, 0);
             questionBytes.CopyTo(queryBytes, headerBytes.Length);
 
@@ -98,15 +99,15 @@ namespace EonaCat.DnsTester.Helpers
         static DnsQuestion ParseDnsQuestionRecord(byte[] queryBytes, ref int offset)
         {
             // Parse the DNS name
-            string name = DnsNameParser.ParseName(queryBytes, ref offset);
+            var name = DnsNameParser.ParseName(queryBytes, ref offset);
             if (name == null)
             {
                 return null;
             }
 
             // Parse the DNS type and class
-            ushort type = (ushort)((queryBytes[offset] << 8) | queryBytes[offset + 1]);
+            var type = (ushort)((queryBytes[offset] << 8) | queryBytes[offset + 1]);
-            ushort qclass = (ushort)((queryBytes[offset + 2] << 8) | queryBytes[offset + 3]);
+            var qclass = (ushort)((queryBytes[offset + 2] << 8) | queryBytes[offset + 3]);
             offset += 4;
 
             return new DnsQuestion
@@ -156,28 +157,28 @@ namespace EonaCat.DnsTester.Helpers
             var offset = 0;
 
             // Parse the DNS header
-            ushort id = (ushort)((responseBytes[0] << 8) | responseBytes[1]);
+            var id = (ushort)((responseBytes[0] << 8) | responseBytes[1]);
-            ushort flags = (ushort)((responseBytes[2] << 8) | responseBytes[3]);
+            var flags = (ushort)((responseBytes[2] << 8) | responseBytes[3]);
-            bool isResponse = (flags & 0x8000) != 0;
+            var isResponse = (flags & 0x8000) != 0;
-            ushort qdcount = (ushort)((responseBytes[4] << 8) | responseBytes[5]);
+            var qdcount = (ushort)((responseBytes[4] << 8) | responseBytes[5]);
-            ushort ancount = (ushort)((responseBytes[6] << 8) | responseBytes[7]);
+            var ancount = (ushort)((responseBytes[6] << 8) | responseBytes[7]);
 
             if (!isResponse)
             {
                 throw new Exception("Invalid DNS response");
             }
 
-            ushort nscount = (ushort)((responseBytes[8] << 8) | responseBytes[9]);
+            var nscount = (ushort)((responseBytes[8] << 8) | responseBytes[9]);
-            ushort arcount = (ushort)((responseBytes[10] << 8) | responseBytes[11]);
+            var arcount = (ushort)((responseBytes[10] << 8) | responseBytes[11]);
             
             // We parsed the header set the offset past the header
             offset = 12;
 
-            List<DnsQuestion> questions = new List<DnsQuestion>();
+            var questions = new List<DnsQuestion>();
 
-            for (int i = 0; i < qdcount; i++)
+            for (var i = 0; i < qdcount; i++)
             {
-                DnsQuestion question = ParseDnsQuestionRecord(responseBytes, ref offset);
+                var question = ParseDnsQuestionRecord(responseBytes, ref offset);
                 if (question != null)
                 {
                     questions.Add(question);
@@ -185,12 +186,12 @@ namespace EonaCat.DnsTester.Helpers
             }
 
             // Parse the DNS answer records
-            List<ResourceRecord> answers = new List<ResourceRecord>();
+            var answers = new List<ResourceRecord>();
-            for (int i = 0; i < ancount; i++)
+            for (var i = 0; i < ancount; i++)
             {
                 try
                 {
-                    ResourceRecord answer = ParseDnsAnswerRecord(responseBytes, ref offset);
+                    var answer = ParseDnsAnswerRecord(responseBytes, ref offset);
                     if (answer != null)
                     {
                         answers.Add(answer);
@@ -203,12 +204,12 @@ namespace EonaCat.DnsTester.Helpers
             }
 
             // Parse the DNS authority records
-            List<ResourceRecord> authorities = new List<ResourceRecord>();
+            var authorities = new List<ResourceRecord>();
-            for (int i = 0; i < nscount; i++)
+            for (var i = 0; i < nscount; i++)
             {
                 try
                 {
-                    ResourceRecord authority = ParseDnsAnswerRecord(responseBytes, ref offset);
+                    var authority = ParseDnsAnswerRecord(responseBytes, ref offset);
                     if (authority != null)
                     {
                         authorities.Add(authority);
@@ -221,12 +222,12 @@ namespace EonaCat.DnsTester.Helpers
             }
 
             // Parse the DNS additional records
-            List<ResourceRecord> additionals = new List<ResourceRecord>();
+            var additionals = new List<ResourceRecord>();
-            for (int i = 0; i < arcount; i++)
+            for (var i = 0; i < arcount; i++)
             {
                 try
                 {
-                    ResourceRecord additional = ParseDnsAnswerRecord(responseBytes, ref offset);
+                    var additional = ParseDnsAnswerRecord(responseBytes, ref offset);
                     if (additional != null)
                     {
                         additionals.Add(additional);
@@ -256,23 +257,23 @@ namespace EonaCat.DnsTester.Helpers
         static ResourceRecord ParseDnsAnswerRecord(byte[] responseBytes, ref int offset)
         {
             // Parse the DNS name
-            string name = DnsNameParser.ExtractDomainName(responseBytes, ref offset);
+            var name = DnsNameParser.ExtractDomainName(responseBytes, ref offset);
             if (name == null)
             {
                 return null;
             }
 
             // Parse the DNS type, class, ttl, and data length
-            DnsRecordType type = (DnsRecordType)((responseBytes[offset++] << 8) + responseBytes[offset++]);
+            var type = (DnsRecordType)((responseBytes[offset++] << 8) + responseBytes[offset++]);
-            DnsRecordClass klass = (DnsRecordClass)((responseBytes[offset++] << 8) + responseBytes[offset++]);
+            var klass = (DnsRecordClass)((responseBytes[offset++] << 8) + responseBytes[offset++]);
-            int ttl = (responseBytes[offset++] << 24) + (responseBytes[offset++] << 16) + (responseBytes[offset++] << 8) + responseBytes[offset++];
+            var ttl = (responseBytes[offset++] << 24) + (responseBytes[offset++] << 16) + (responseBytes[offset++] << 8) + responseBytes[offset++];
 
             // Extract record data length
-            int dataLength = (responseBytes[offset] << 8) + responseBytes[offset + 1];
+            var dataLength = (responseBytes[offset] << 8) + responseBytes[offset + 1];
             offset += 2;
 
             // Extract record data
-            byte[] recordData = new byte[dataLength];
+            var recordData = new byte[dataLength];
             Buffer.BlockCopy(responseBytes, offset, recordData, 0, dataLength);
 
             string recordDataAsString = null;
@@ -293,9 +294,9 @@ namespace EonaCat.DnsTester.Helpers
                     recordDataAsString = DnsNameParser.ExtractDomainName(responseBytes, ref offset);
                     break;
                 case DnsRecordType.MX:
-                    int preference = (responseBytes[0] << 8) + responseBytes[1];
+                    var preference = (responseBytes[0] << 8) + responseBytes[1];
                     offset += 2;
-                    string exchange = DnsNameParser.ExtractDomainName(responseBytes, ref offset);
+                    var exchange = DnsNameParser.ExtractDomainName(responseBytes, ref offset);
                     recordDataAsString = $"{preference} {exchange}";
                     break;
                 case DnsRecordType.TXT:
@@ -318,8 +319,8 @@ namespace EonaCat.DnsTester.Helpers
 
         static string GetString(byte[] bytes, ref int index, int length)
         {
-            string str = "";
+            var str = "";
-            for (int i = 0; i < length; i++)
+            for (var i = 0; i < length; i++)
             {
                 str += (char)bytes[index++];
             }

EonaCat.DnsTester/Helpers/DnsNameParser.cs

@@ -7,7 +7,7 @@ namespace EonaCat.DnsTester.Helpers
     {
         public static string ParseName(byte[] responseBytes, ref int offset)
         {
-            List<string> labels = new List<string>();
+            var labels = new List<string>();
             int length;
 
             while ((length = responseBytes[offset++]) != 0)
@@ -15,8 +15,8 @@ namespace EonaCat.DnsTester.Helpers
                 if ((length & 0xC0) == 0xC0)
                 {
                     // The name is compressed
-                    int pointer = ((length & 0x3F) << 8) | responseBytes[offset++];
+                    var pointer = ((length & 0x3F) << 8) | responseBytes[offset++];
-                    int savedOffset = offset;
+                    var savedOffset = offset;
                     offset = pointer;
                     labels.AddRange(ParseName(responseBytes, ref offset).Split('.'));
                     offset = savedOffset;
@@ -24,7 +24,7 @@ namespace EonaCat.DnsTester.Helpers
                 }
 
                 // The name is not compressed
-                labels.Add(System.Text.Encoding.ASCII.GetString(responseBytes, offset, length));
+                labels.Add(Encoding.ASCII.GetString(responseBytes, offset, length));
                 offset += length;
             }
 
@@ -33,11 +33,11 @@ namespace EonaCat.DnsTester.Helpers
 
         public static string ExtractDomainName(byte[] buffer, ref int offset)
         {
-            List<string> labels = new List<string>();
+            var labels = new List<string>();
 
             while (true)
             {
-                byte labelLength = buffer[offset++];
+                var labelLength = buffer[offset++];
 
                 if (labelLength == 0)
                 {
@@ -47,12 +47,12 @@ namespace EonaCat.DnsTester.Helpers
                 if ((labelLength & 0xC0) == 0xC0)
                 {
                     // Compressed domain name
-                    int pointer = (int)(((labelLength & 0x3F) << 8) + buffer[offset++]);
+                    var pointer = (int)(((labelLength & 0x3F) << 8) + buffer[offset++]);
                     labels.Add(ExtractDomainName(buffer, ref pointer));
                     break;
                 }
 
-                string label = Encoding.ASCII.GetString(buffer, offset, labelLength);
+                var label = Encoding.ASCII.GetString(buffer, offset, labelLength);
                 labels.Add(label);
                 offset += labelLength;
             }

EonaCat.DnsTester/Helpers/UrlHelper.cs

@@ -1,7 +1,8 @@
 using System;
+using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Linq;
-using System.Net;
+using System.Net.Http;
 using System.Security.Cryptography;
 using System.Text.RegularExpressions;
 using System.Threading.Tasks;
@@ -10,111 +11,147 @@ namespace EonaCat.DnsTester.Helpers
 {
     internal class UrlHelper
     {
-        private static readonly RandomNumberGenerator _randomNumberGenerator = RandomNumberGenerator.Create();
+        private static readonly RandomNumberGenerator RandomNumberGenerator = RandomNumberGenerator.Create();
         public static event EventHandler<string> Log;
 
-        private static async Task<List<string>> GetRandomUrls(int totalUrls)
+        public static bool UseSearchEngineYahoo { get; set; }
+        public static bool UseSearchEngineBing { get; set; }
+        public static bool UseSearchEngineGoogle { get; set; }
+        public static bool UseSearchEngineQwant { get; set; }
+        public static bool UseSearchEngineWolfram { get; set; }
+        public static bool UseSearchEngineStartPage { get; set; }
+        public static bool UseSearchEngineYandex { get; set; }
+
+
+    private static async Task<List<string>> GetRandomUrlsAsync(int totalUrls)
     {
+        var urls = new ConcurrentDictionary<string, byte>();
         var letters = GetRandomLetters();
+        var searchEngineUrls = GetSearchEngines().ToList();
+        var random = new Random();
 
-            Dictionary<string, string> searchEngineUrls = new Dictionary<string, string>
+        while (urls.Count < totalUrls && searchEngineUrls.Count > 0)
         {
-                { "Yahoo", "https://search.yahoo.com/search?p=" },
+            await Task.Run(async () =>
-                { "Bing", "https://www.bing.com/search?q=" },
-                { "Google", "https://www.google.com/search?q=" },
-                { "Ask", "https://www.ask.com/web?q=" },
-                { "WolframAlpha", "https://www.wolframalpha.com/input/?i=" },
-                { "StartPage", "https://www.startpage.com/do/dsearch?query=" },
-                { "Yandex", "https://www.yandex.com/search/?text=" },
-                { "Qwant", "https://www.qwant.com/?q=" }
-            };
-
-            Random rand = new Random();
-
-            List<string> urls = new List<string>();
-            while (urls.Count < totalUrls)
             {
-                int index = rand.Next(searchEngineUrls.Count);
+                var index = random.Next(searchEngineUrls.Count);
-                KeyValuePair<string, string> searchEngine = searchEngineUrls.ElementAt(index);
+                var searchEngine = searchEngineUrls[index];
-
+                var url = searchEngine.Value + letters;
-                string url = searchEngine.Value + letters;
 
                 try
                 {
-                    using (var client = new WebClient())
+                    var httpClient = new HttpClient();
+                    var response = await httpClient.GetAsync(url).ConfigureAwait(false);
+
+                    if (response.IsSuccessStatusCode)
                     {
-                        string responseString = client.DownloadString(url);
+                        var responseString = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
+                        var hostNames = Regex.Matches(responseString, @"[.](\w+[.]com)");
 
-                        // find all .xxx.com addresses
-                        MatchCollection hostNames = Regex.Matches(responseString, @"[.](\w+[.]com)");
-
-                        // Loop through the match collection to retrieve all matches and delete the leading "."
-                        HashSet<string> uniqueNames = new HashSet<string>();
                         foreach (Match match in hostNames)
                         {
-                            string name = match.Groups[1].Value;
+                            var name = match.Groups[1].Value;
-                            if (name != $"{searchEngine.Key.ToLower()}.com")
+                            if (name == $"{searchEngine.Key.ToLower()}.com") continue;
-                            {
-                                uniqueNames.Add(name);
-                            }
-                        }
 
-                        // Add the names to the list
+                            urls.TryAdd(name, 0); // TryAdd is thread-safe
-                        foreach (string name in uniqueNames)
-                        {
                             if (urls.Count >= totalUrls)
                             {
                                 break;
                             }
-
+                        }
-                            if (!urls.Contains(name))
+                    }
+                    else
                     {
-                                urls.Add(name);
+                        searchEngineUrls.RemoveAt(index);
-                            }
+                        SetStatus($"{searchEngine.Key}: {response.StatusCode}");
-                        }
                     }
 
-                    await Task.Delay(100);
+                    httpClient.Dispose();
                 }
                 catch (Exception ex)
                 {
-                    searchEngineUrls.Remove(searchEngine.Key);
+                    searchEngineUrls.RemoveAt(index);
                     SetStatus($"{searchEngine.Key}: {ex.Message}");
                 }
-                finally
+
-                {
                 letters = GetRandomLetters();
-                }
+                await Task.Delay(100).ConfigureAwait(false);
+            }).ConfigureAwait(false);
         }
 
         var urlText = "url" + (urls.Count > 1 ? "'s" : string.Empty);
         SetStatus($"{urls.Count} random {urlText} found");
-            return urls;
+        return urls.Keys.ToList();
     }
 
-        public static async Task<List<string>> RetrieveUrls(int numThreads, int numUrlsPerThread)
-        {
-            Task[] tasks = new Task[numThreads];
 
-            List<string> urlList = new List<string>();
 
-            // start each thread to retrieve a subset of unique URLs
+    private static Dictionary<string, string> GetSearchEngines()
-            for (int i = 0; i < numThreads; i++)
         {
-                tasks[i] = Task.Run(async () => urlList.AddRange(await GetRandomUrls(numUrlsPerThread)));
+            var searchEngineUrls = new Dictionary<string, string>();
+            if (UseSearchEngineYahoo)
+            {
+                searchEngineUrls.Add("Yahoo", "https://search.yahoo.com/search?p=");
             }
 
-            // wait for all threads to complete
+            if (UseSearchEngineBing)
-            await Task.WhenAll(tasks);
+            {
+                searchEngineUrls.Add("Bing", "https://www.bing.com/search?q=");
+            }
+
+            if (UseSearchEngineGoogle)
+            {
+                searchEngineUrls.Add("Google", "https://www.google.com/search?q=");
+            }
+
+            if (UseSearchEngineQwant)
+            {
+                searchEngineUrls.Add("Qwant", "https://www.qwant.com/?q=");
+            }
+
+            if (UseSearchEngineWolfram)
+            {
+                searchEngineUrls.Add("WolframAlpha", "https://www.wolframalpha.com/input/?i=");
+            }
+
+            if (UseSearchEngineStartPage)
+            {
+                searchEngineUrls.Add("StartPage", "https://www.startpage.com/do/dsearch?query=");
+            }
+
+            if (UseSearchEngineYandex)
+            {
+                searchEngineUrls.Add("Yandex", "https://www.yandex.com/search/?text=");
+            }
+
+            return searchEngineUrls;
+        }
+
+        public static async Task<List<string>> RetrieveUrlsAsync(int numThreads, int numUrlsPerThread)
+        {
+            var tasks = new List<Task<List<string>>>();
+
+            // Start each task to retrieve a subset of unique URLs
+            for (var i = 0; i < numThreads; i++)
+            {
+                tasks.Add(GetRandomUrlsAsync(numUrlsPerThread));
+            }
+
+            // Wait for all tasks to complete
+            var results = await Task.WhenAll(tasks).ConfigureAwait(false);
+
+            // Flatten the results from all tasks into a single list
+            var urlList = results.SelectMany(urls => urls).ToList();
 
             return urlList;
         }
 
+
         private static string GetRandomLetters()
         {
             // Generate a cryptographically strong random string
-            byte[] randomBytes = new byte[32];
+            var randomBytes = new byte[32];
-            _randomNumberGenerator.GetBytes(randomBytes);
+            RandomNumberGenerator.GetBytes(randomBytes);
             return Convert.ToBase64String(randomBytes);
         }
 

EonaCat.DnsTester/MainForm.Designer.cs

@@ -30,7 +30,27 @@
         {
             System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(MainForm));
             RunTest = new System.Windows.Forms.Button();
+            tabControl1 = new System.Windows.Forms.TabControl();
+            tabPage1 = new System.Windows.Forms.TabPage();
+            panel2 = new System.Windows.Forms.Panel();
+            checkBox8 = new System.Windows.Forms.CheckBox();
+            checkBox7 = new System.Windows.Forms.CheckBox();
+            checkBox6 = new System.Windows.Forms.CheckBox();
+            checkBox5 = new System.Windows.Forms.CheckBox();
+            checkBox3 = new System.Windows.Forms.CheckBox();
+            checkBox2 = new System.Windows.Forms.CheckBox();
+            checkBox1 = new System.Windows.Forms.CheckBox();
+            label4 = new System.Windows.Forms.Label();
+            StatusBox = new System.Windows.Forms.ListBox();
+            ResultView = new System.Windows.Forms.ListView();
+            Url = new System.Windows.Forms.ColumnHeader();
+            DNS1DATA = new System.Windows.Forms.ColumnHeader();
+            DNS1Performance = new System.Windows.Forms.ColumnHeader();
+            DNS2DATA = new System.Windows.Forms.ColumnHeader();
+            DNS2Performance = new System.Windows.Forms.ColumnHeader();
             panel1 = new System.Windows.Forms.Panel();
+            numericUpDown2 = new System.Windows.Forms.NumericUpDown();
+            label2 = new System.Windows.Forms.Label();
             comboBox1 = new System.Windows.Forms.ComboBox();
             numericUpDown1 = new System.Windows.Forms.NumericUpDown();
             label3 = new System.Windows.Forms.Label();
@@ -45,14 +65,7 @@
             dnsList1 = new System.Windows.Forms.ComboBox();
             lblDns2 = new System.Windows.Forms.Label();
             lblDns1 = new System.Windows.Forms.Label();
-            panel2 = new System.Windows.Forms.Panel();
+            tabPage2 = new System.Windows.Forms.TabPage();
-            StatusBox = new System.Windows.Forms.ListBox();
-            ResultView = new System.Windows.Forms.ListView();
-            Url = new System.Windows.Forms.ColumnHeader();
-            DNS1DATA = new System.Windows.Forms.ColumnHeader();
-            DNS1Performance = new System.Windows.Forms.ColumnHeader();
-            DNS2DATA = new System.Windows.Forms.ColumnHeader();
-            DNS2Performance = new System.Windows.Forms.ColumnHeader();
             panel3 = new System.Windows.Forms.Panel();
             btnResolveHost = new System.Windows.Forms.Button();
             btnResolveIP = new System.Windows.Forms.Button();
@@ -60,13 +73,14 @@
             txtResolveIP = new System.Windows.Forms.TextBox();
             label5 = new System.Windows.Forms.Label();
             label1 = new System.Windows.Forms.Label();
-            label2 = new System.Windows.Forms.Label();
+            tabControl1.SuspendLayout();
-            numericUpDown2 = new System.Windows.Forms.NumericUpDown();
+            tabPage1.SuspendLayout();
-            panel1.SuspendLayout();
-            ((System.ComponentModel.ISupportInitialize)numericUpDown1).BeginInit();
             panel2.SuspendLayout();
-            panel3.SuspendLayout();
+            panel1.SuspendLayout();
             ((System.ComponentModel.ISupportInitialize)numericUpDown2).BeginInit();
+            ((System.ComponentModel.ISupportInitialize)numericUpDown1).BeginInit();
+            tabPage2.SuspendLayout();
+            panel3.SuspendLayout();
             SuspendLayout();
             // 
             // RunTest
@@ -77,13 +91,204 @@
             RunTest.Name = "RunTest";
             RunTest.Size = new System.Drawing.Size(435, 115);
             RunTest.TabIndex = 12;
-            RunTest.Text = "Run Test";
+            RunTest.Text = "Execute";
             RunTest.UseVisualStyleBackColor = false;
             RunTest.Click += RunTest_Click;
             // 
+            // tabControl1
+            // 
+            tabControl1.Controls.Add(tabPage1);
+            tabControl1.Controls.Add(tabPage2);
+            tabControl1.Location = new System.Drawing.Point(105, 0);
+            tabControl1.Name = "tabControl1";
+            tabControl1.SelectedIndex = 0;
+            tabControl1.Size = new System.Drawing.Size(2259, 1517);
+            tabControl1.TabIndex = 27;
+            // 
+            // tabPage1
+            // 
+            tabPage1.BackColor = System.Drawing.Color.LightGray;
+            tabPage1.Controls.Add(panel2);
+            tabPage1.Controls.Add(panel1);
+            tabPage1.Location = new System.Drawing.Point(10, 58);
+            tabPage1.Name = "tabPage1";
+            tabPage1.Padding = new System.Windows.Forms.Padding(3);
+            tabPage1.Size = new System.Drawing.Size(2239, 1449);
+            tabPage1.TabIndex = 0;
+            tabPage1.Text = "Dns tester";
+            // 
+            // panel2
+            // 
+            panel2.BackColor = System.Drawing.Color.Gold;
+            panel2.Controls.Add(checkBox8);
+            panel2.Controls.Add(checkBox7);
+            panel2.Controls.Add(checkBox6);
+            panel2.Controls.Add(checkBox5);
+            panel2.Controls.Add(checkBox3);
+            panel2.Controls.Add(checkBox2);
+            panel2.Controls.Add(checkBox1);
+            panel2.Controls.Add(label4);
+            panel2.Controls.Add(StatusBox);
+            panel2.Controls.Add(ResultView);
+            panel2.Location = new System.Drawing.Point(50, 510);
+            panel2.Name = "panel2";
+            panel2.Size = new System.Drawing.Size(2142, 905);
+            panel2.TabIndex = 27;
+            // 
+            // checkBox8
+            // 
+            checkBox8.AutoSize = true;
+            checkBox8.Checked = true;
+            checkBox8.CheckState = System.Windows.Forms.CheckState.Checked;
+            checkBox8.Location = new System.Drawing.Point(1172, 38);
+            checkBox8.Name = "checkBox8";
+            checkBox8.Size = new System.Drawing.Size(143, 45);
+            checkBox8.TabIndex = 70;
+            checkBox8.Text = "Qwant";
+            checkBox8.UseVisualStyleBackColor = true;
+            // 
+            // checkBox7
+            // 
+            checkBox7.AutoSize = true;
+            checkBox7.Checked = true;
+            checkBox7.CheckState = System.Windows.Forms.CheckState.Checked;
+            checkBox7.Location = new System.Drawing.Point(1172, 135);
+            checkBox7.Name = "checkBox7";
+            checkBox7.Size = new System.Drawing.Size(150, 45);
+            checkBox7.TabIndex = 69;
+            checkBox7.Text = "Yandex";
+            checkBox7.UseVisualStyleBackColor = true;
+            // 
+            // checkBox6
+            // 
+            checkBox6.AutoSize = true;
+            checkBox6.Checked = true;
+            checkBox6.CheckState = System.Windows.Forms.CheckState.Checked;
+            checkBox6.Location = new System.Drawing.Point(959, 135);
+            checkBox6.Name = "checkBox6";
+            checkBox6.Size = new System.Drawing.Size(181, 45);
+            checkBox6.TabIndex = 68;
+            checkBox6.Text = "StartPage";
+            checkBox6.UseVisualStyleBackColor = true;
+            // 
+            // checkBox5
+            // 
+            checkBox5.AutoSize = true;
+            checkBox5.Checked = true;
+            checkBox5.CheckState = System.Windows.Forms.CheckState.Checked;
+            checkBox5.Location = new System.Drawing.Point(659, 135);
+            checkBox5.Name = "checkBox5";
+            checkBox5.Size = new System.Drawing.Size(244, 45);
+            checkBox5.TabIndex = 67;
+            checkBox5.Text = "WolframAlpha";
+            checkBox5.UseVisualStyleBackColor = true;
+            // 
+            // checkBox3
+            // 
+            checkBox3.AutoSize = true;
+            checkBox3.Checked = true;
+            checkBox3.CheckState = System.Windows.Forms.CheckState.Checked;
+            checkBox3.Location = new System.Drawing.Point(959, 42);
+            checkBox3.Name = "checkBox3";
+            checkBox3.Size = new System.Drawing.Size(154, 45);
+            checkBox3.TabIndex = 65;
+            checkBox3.Text = "Google";
+            checkBox3.UseVisualStyleBackColor = true;
+            // 
+            // checkBox2
+            // 
+            checkBox2.AutoSize = true;
+            checkBox2.Checked = true;
+            checkBox2.CheckState = System.Windows.Forms.CheckState.Checked;
+            checkBox2.Location = new System.Drawing.Point(819, 41);
+            checkBox2.Name = "checkBox2";
+            checkBox2.Size = new System.Drawing.Size(115, 45);
+            checkBox2.TabIndex = 64;
+            checkBox2.Text = "Bing";
+            checkBox2.UseVisualStyleBackColor = true;
+            // 
+            // checkBox1
+            // 
+            checkBox1.AutoSize = true;
+            checkBox1.Checked = true;
+            checkBox1.CheckState = System.Windows.Forms.CheckState.Checked;
+            checkBox1.Location = new System.Drawing.Point(659, 42);
+            checkBox1.Name = "checkBox1";
+            checkBox1.Size = new System.Drawing.Size(138, 45);
+            checkBox1.TabIndex = 63;
+            checkBox1.Text = "Yahoo";
+            checkBox1.UseVisualStyleBackColor = true;
+            // 
+            // label4
+            // 
+            label4.AutoSize = true;
+            label4.Location = new System.Drawing.Point(56, 42);
+            label4.Margin = new System.Windows.Forms.Padding(8, 0, 8, 0);
+            label4.Name = "label4";
+            label4.Size = new System.Drawing.Size(472, 41);
+            label4.TabIndex = 62;
+            label4.Text = "Use searchengines for url retrieval:";
+            label4.Visible = false;
+            // 
+            // StatusBox
+            // 
+            StatusBox.BackColor = System.Drawing.Color.OldLace;
+            StatusBox.FormattingEnabled = true;
+            StatusBox.HorizontalScrollbar = true;
+            StatusBox.ItemHeight = 41;
+            StatusBox.Location = new System.Drawing.Point(56, 741);
+            StatusBox.Margin = new System.Windows.Forms.Padding(8, 7, 8, 7);
+            StatusBox.Name = "StatusBox";
+            StatusBox.Size = new System.Drawing.Size(2051, 127);
+            StatusBox.TabIndex = 25;
+            // 
+            // ResultView
+            // 
+            ResultView.BackColor = System.Drawing.Color.OldLace;
+            ResultView.Columns.AddRange(new System.Windows.Forms.ColumnHeader[] { Url, DNS1DATA, DNS1Performance, DNS2DATA, DNS2Performance });
+            ResultView.GridLines = true;
+            ResultView.HeaderStyle = System.Windows.Forms.ColumnHeaderStyle.Nonclickable;
+            ResultView.Location = new System.Drawing.Point(56, 214);
+            ResultView.Margin = new System.Windows.Forms.Padding(8, 7, 8, 7);
+            ResultView.MultiSelect = false;
+            ResultView.Name = "ResultView";
+            ResultView.Size = new System.Drawing.Size(2051, 487);
+            ResultView.TabIndex = 24;
+            ResultView.UseCompatibleStateImageBehavior = false;
+            ResultView.View = System.Windows.Forms.View.Details;
+            // 
+            // Url
+            // 
+            Url.Text = "URL";
+            Url.Width = 160;
+            // 
+            // DNS1DATA
+            // 
+            DNS1DATA.Text = "Data";
+            DNS1DATA.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
+            DNS1DATA.Width = 140;
+            // 
+            // DNS1Performance
+            // 
+            DNS1Performance.Text = "Performance";
+            DNS1Performance.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
+            DNS1Performance.Width = 120;
+            // 
+            // DNS2DATA
+            // 
+            DNS2DATA.Text = "Data";
+            DNS2DATA.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
+            DNS2DATA.Width = 140;
+            // 
+            // DNS2Performance
+            // 
+            DNS2Performance.Text = "Performance";
+            DNS2Performance.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
+            DNS2Performance.Width = 120;
+            // 
             // panel1
             // 
-            panel1.BackColor = System.Drawing.SystemColors.ControlLight;
+            panel1.BackColor = System.Drawing.Color.Gold;
             panel1.Controls.Add(numericUpDown2);
             panel1.Controls.Add(label2);
             panel1.Controls.Add(comboBox1);
@@ -100,19 +305,40 @@
             panel1.Controls.Add(dnsList1);
             panel1.Controls.Add(lblDns2);
             panel1.Controls.Add(lblDns1);
-            panel1.Location = new System.Drawing.Point(155, 294);
+            panel1.Location = new System.Drawing.Point(50, 49);
             panel1.Name = "panel1";
-            panel1.Size = new System.Drawing.Size(2209, 396);
+            panel1.Size = new System.Drawing.Size(2142, 396);
-            panel1.TabIndex = 24;
+            panel1.TabIndex = 26;
+            // 
+            // numericUpDown2
+            // 
+            numericUpDown2.Location = new System.Drawing.Point(804, 228);
+            numericUpDown2.Maximum = new decimal(new int[] { 1000000000, 0, 0, 0 });
+            numericUpDown2.Minimum = new decimal(new int[] { 1, 0, 0, 0 });
+            numericUpDown2.Name = "numericUpDown2";
+            numericUpDown2.Size = new System.Drawing.Size(120, 47);
+            numericUpDown2.TabIndex = 61;
+            numericUpDown2.Value = new decimal(new int[] { 5, 0, 0, 0 });
+            // 
+            // label2
+            // 
+            label2.AutoSize = true;
+            label2.Location = new System.Drawing.Point(566, 228);
+            label2.Name = "label2";
+            label2.Size = new System.Drawing.Size(201, 41);
+            label2.TabIndex = 60;
+            label2.Text = "Total Threads:";
             // 
             // comboBox1
             // 
+            comboBox1.ForeColor = System.Drawing.Color.Black;
             comboBox1.FormattingEnabled = true;
             comboBox1.Items.AddRange(new object[] { "A", "NS", "CNAME", "MX", "TXT" });
             comboBox1.Location = new System.Drawing.Point(1583, 71);
             comboBox1.Name = "comboBox1";
             comboBox1.Size = new System.Drawing.Size(302, 49);
             comboBox1.TabIndex = 59;
+            comboBox1.Text = "Select record type";
             comboBox1.SelectedIndexChanged += comboBox1_SelectedIndexChanged;
             // 
             // numericUpDown1
@@ -163,7 +389,7 @@
             // CustomDns2
             // 
             CustomDns2.Enabled = false;
-            CustomDns2.Location = new System.Drawing.Point(1318, 297);
+            CustomDns2.Location = new System.Drawing.Point(1317, 289);
             CustomDns2.Margin = new System.Windows.Forms.Padding(8, 7, 8, 7);
             CustomDns2.Name = "CustomDns2";
             CustomDns2.Size = new System.Drawing.Size(668, 47);
@@ -184,7 +410,7 @@
             // lblCustom2
             // 
             lblCustom2.AutoSize = true;
-            lblCustom2.Location = new System.Drawing.Point(1065, 301);
+            lblCustom2.Location = new System.Drawing.Point(1064, 293);
             lblCustom2.Margin = new System.Windows.Forms.Padding(8, 0, 8, 0);
             lblCustom2.Name = "lblCustom2";
             lblCustom2.Size = new System.Drawing.Size(219, 41);
@@ -206,7 +432,7 @@
             // UseCustomServers
             // 
             UseCustomServers.AutoSize = true;
-            UseCustomServers.Location = new System.Drawing.Point(1723, 147);
+            UseCustomServers.Location = new System.Drawing.Point(1071, 224);
             UseCustomServers.Margin = new System.Windows.Forms.Padding(8, 7, 8, 7);
             UseCustomServers.Name = "UseCustomServers";
             UseCustomServers.Size = new System.Drawing.Size(262, 45);
@@ -224,6 +450,7 @@
             dnsList2.Name = "dnsList2";
             dnsList2.Size = new System.Drawing.Size(320, 49);
             dnsList2.TabIndex = 38;
+            dnsList2.Text = "Select Dns2";
             // 
             // dnsList1
             // 
@@ -234,6 +461,7 @@
             dnsList1.Name = "dnsList1";
             dnsList1.Size = new System.Drawing.Size(451, 49);
             dnsList1.TabIndex = 37;
+            dnsList1.Text = "Select Dns 1";
             // 
             // lblDns2
             // 
@@ -255,69 +483,16 @@
             lblDns1.TabIndex = 35;
             lblDns1.Text = "Dns 1:";
             // 
-            // panel2
+            // tabPage2
             // 
-            panel2.BackColor = System.Drawing.SystemColors.ControlLight;
+            tabPage2.Controls.Add(panel3);
-            panel2.Controls.Add(StatusBox);
+            tabPage2.Location = new System.Drawing.Point(10, 58);
-            panel2.Controls.Add(ResultView);
+            tabPage2.Name = "tabPage2";
-            panel2.Location = new System.Drawing.Point(145, 765);
+            tabPage2.Padding = new System.Windows.Forms.Padding(3);
-            panel2.Name = "panel2";
+            tabPage2.Size = new System.Drawing.Size(2239, 1449);
-            panel2.Size = new System.Drawing.Size(2219, 745);
+            tabPage2.TabIndex = 1;
-            panel2.TabIndex = 25;
+            tabPage2.Text = "Resolve clients";
-            // 
+            tabPage2.UseVisualStyleBackColor = true;
-            // StatusBox
-            // 
-            StatusBox.FormattingEnabled = true;
-            StatusBox.HorizontalScrollbar = true;
-            StatusBox.ItemHeight = 41;
-            StatusBox.Location = new System.Drawing.Point(56, 571);
-            StatusBox.Margin = new System.Windows.Forms.Padding(8, 7, 8, 7);
-            StatusBox.Name = "StatusBox";
-            StatusBox.Size = new System.Drawing.Size(2126, 127);
-            StatusBox.TabIndex = 25;
-            // 
-            // ResultView
-            // 
-            ResultView.Columns.AddRange(new System.Windows.Forms.ColumnHeader[] { Url, DNS1DATA, DNS1Performance, DNS2DATA, DNS2Performance });
-            ResultView.GridLines = true;
-            ResultView.HeaderStyle = System.Windows.Forms.ColumnHeaderStyle.Nonclickable;
-            ResultView.Location = new System.Drawing.Point(56, 49);
-            ResultView.Margin = new System.Windows.Forms.Padding(8, 7, 8, 7);
-            ResultView.MultiSelect = false;
-            ResultView.Name = "ResultView";
-            ResultView.Size = new System.Drawing.Size(2126, 487);
-            ResultView.TabIndex = 24;
-            ResultView.UseCompatibleStateImageBehavior = false;
-            ResultView.View = System.Windows.Forms.View.Details;
-            // 
-            // Url
-            // 
-            Url.Text = "URL";
-            Url.Width = 160;
-            // 
-            // DNS1DATA
-            // 
-            DNS1DATA.Text = "Data";
-            DNS1DATA.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
-            DNS1DATA.Width = 140;
-            // 
-            // DNS1Performance
-            // 
-            DNS1Performance.Text = "Performance";
-            DNS1Performance.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
-            DNS1Performance.Width = 120;
-            // 
-            // DNS2DATA
-            // 
-            DNS2DATA.Text = "Data";
-            DNS2DATA.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
-            DNS2DATA.Width = 140;
-            // 
-            // DNS2Performance
-            // 
-            DNS2Performance.Text = "Performance";
-            DNS2Performance.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
-            DNS2Performance.Width = 120;
             // 
             // panel3
             // 
@@ -328,10 +503,10 @@
             panel3.Controls.Add(txtResolveIP);
             panel3.Controls.Add(label5);
             panel3.Controls.Add(label1);
-            panel3.Location = new System.Drawing.Point(155, 45);
+            panel3.Location = new System.Drawing.Point(15, 12);
             panel3.Name = "panel3";
             panel3.Size = new System.Drawing.Size(2209, 175);
-            panel3.TabIndex = 26;
+            panel3.TabIndex = 28;
             // 
             // btnResolveHost
             // 
@@ -385,35 +560,15 @@
             label1.TabIndex = 66;
             label1.Text = "Resolve ip address:";
             // 
-            // label2
-            // 
-            label2.AutoSize = true;
-            label2.Location = new System.Drawing.Point(566, 228);
-            label2.Name = "label2";
-            label2.Size = new System.Drawing.Size(201, 41);
-            label2.TabIndex = 60;
-            label2.Text = "Total Threads:";
-            // 
-            // numericUpDown2
-            // 
-            numericUpDown2.Location = new System.Drawing.Point(804, 228);
-            numericUpDown2.Maximum = new decimal(new int[] { 1000000000, 0, 0, 0 });
-            numericUpDown2.Minimum = new decimal(new int[] { 1, 0, 0, 0 });
-            numericUpDown2.Name = "numericUpDown2";
-            numericUpDown2.Size = new System.Drawing.Size(120, 47);
-            numericUpDown2.TabIndex = 61;
-            numericUpDown2.Value = new decimal(new int[] { 5, 0, 0, 0 });
-            // 
             // MainForm
             // 
             AutoScaleDimensions = new System.Drawing.SizeF(240F, 240F);
             AutoScaleMode = System.Windows.Forms.AutoScaleMode.Dpi;
             AutoSize = true;
             AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink;
+            BackColor = System.Drawing.SystemColors.MenuHighlight;
             ClientSize = new System.Drawing.Size(2517, 1693);
-            Controls.Add(panel3);
+            Controls.Add(tabControl1);
-            Controls.Add(panel2);
-            Controls.Add(panel1);
             Controls.Add(RunTest);
             Icon = (System.Drawing.Icon)resources.GetObject("$this.Icon");
             Margin = new System.Windows.Forms.Padding(8, 7, 8, 7);
@@ -422,19 +577,35 @@
             StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
             Text = "EonaCat.DnsTester";
             Load += TesterUI_Load;
+            tabControl1.ResumeLayout(false);
+            tabPage1.ResumeLayout(false);
+            panel2.ResumeLayout(false);
+            panel2.PerformLayout();
             panel1.ResumeLayout(false);
             panel1.PerformLayout();
+            ((System.ComponentModel.ISupportInitialize)numericUpDown2).EndInit();
             ((System.ComponentModel.ISupportInitialize)numericUpDown1).EndInit();
-            panel2.ResumeLayout(false);
+            tabPage2.ResumeLayout(false);
             panel3.ResumeLayout(false);
             panel3.PerformLayout();
-            ((System.ComponentModel.ISupportInitialize)numericUpDown2).EndInit();
             ResumeLayout(false);
         }
 
         #endregion
         private System.Windows.Forms.Button RunTest;
+        private System.Windows.Forms.TabControl tabControl1;
+        private System.Windows.Forms.TabPage tabPage1;
+        private System.Windows.Forms.Panel panel2;
+        private System.Windows.Forms.ListBox StatusBox;
+        private System.Windows.Forms.ListView ResultView;
+        private System.Windows.Forms.ColumnHeader Url;
+        private System.Windows.Forms.ColumnHeader DNS1DATA;
+        private System.Windows.Forms.ColumnHeader DNS1Performance;
+        private System.Windows.Forms.ColumnHeader DNS2DATA;
+        private System.Windows.Forms.ColumnHeader DNS2Performance;
         private System.Windows.Forms.Panel panel1;
+        private System.Windows.Forms.NumericUpDown numericUpDown2;
+        private System.Windows.Forms.Label label2;
         private System.Windows.Forms.ComboBox comboBox1;
         private System.Windows.Forms.NumericUpDown numericUpDown1;
         private System.Windows.Forms.Label label3;
@@ -449,14 +620,7 @@
         private System.Windows.Forms.ComboBox dnsList1;
         private System.Windows.Forms.Label lblDns2;
         private System.Windows.Forms.Label lblDns1;
-        private System.Windows.Forms.Panel panel2;
+        private System.Windows.Forms.TabPage tabPage2;
-        private System.Windows.Forms.ListBox StatusBox;
-        private System.Windows.Forms.ListView ResultView;
-        private System.Windows.Forms.ColumnHeader Url;
-        private System.Windows.Forms.ColumnHeader DNS1DATA;
-        private System.Windows.Forms.ColumnHeader DNS1Performance;
-        private System.Windows.Forms.ColumnHeader DNS2DATA;
-        private System.Windows.Forms.ColumnHeader DNS2Performance;
         private System.Windows.Forms.Panel panel3;
         private System.Windows.Forms.Button btnResolveHost;
         private System.Windows.Forms.Button btnResolveIP;
@@ -464,8 +628,14 @@
         private System.Windows.Forms.TextBox txtResolveIP;
         private System.Windows.Forms.Label label5;
         private System.Windows.Forms.Label label1;
-        private System.Windows.Forms.NumericUpDown numericUpDown2;
+        private System.Windows.Forms.Label label4;
-        private System.Windows.Forms.Label label2;
+        private System.Windows.Forms.CheckBox checkBox1;
+        private System.Windows.Forms.CheckBox checkBox2;
+        private System.Windows.Forms.CheckBox checkBox3;
+        private System.Windows.Forms.CheckBox checkBox8;
+        private System.Windows.Forms.CheckBox checkBox7;
+        private System.Windows.Forms.CheckBox checkBox6;
+        private System.Windows.Forms.CheckBox checkBox5;
     }
 }
 

EonaCat.DnsTester/MainForm.cs

@@ -37,33 +37,43 @@ namespace EonaCat.DnsTester
                 }
             }
 
-            if (_useCustomDnsServers && (!chkDns1.Checked || chkDns2.Checked))
+            if (_useCustomDnsServers && (!chkDns1.Checked && !chkDns2.Checked))
             {
                 MessageBox.Show("Please enable DNS 1 or 2 before using custom Dns");
                 return;
             }
 
-            List<string> urls = new List<string>();
             SetupView();
 
-
+            var numThreads = (int)numericUpDown2.Value; // number of concurrent threads to use
-            int numThreads = (int)numericUpDown2.Value; // number of concurrent threads to use
+            var maxUrls = (int)numericUpDown1.Value; // maximum number of unique URLs to retrieve
-            int maxUrls = (int)numericUpDown1.Value; // maximum number of unique URLs to retrieve
+            var numUrlsPerThread = maxUrls / numThreads;
-            int numUrlsPerThread = maxUrls / numThreads;
+            if (numUrlsPerThread == 0)
-
-
-            urls = await UrlHelper.RetrieveUrls(numThreads, numUrlsPerThread);
-            AddUrlToView(urls);
-
-
-            if (IsRunning)
             {
-                return;
+                numUrlsPerThread = maxUrls;
+                numThreads = 1;
             }
 
+            SetSearchEngines();
+            var urls = await UrlHelper.RetrieveUrlsAsync(numThreads, numUrlsPerThread).ConfigureAwait(false);
+            AddUrlToView(urls);
+
             IsRunning = true;
-            await Process(_recordType, urls.ToArray(), _dnsServer1, _dnsServer2);
+            RunTest.Invoke(() => { RunTest.Enabled = false; });
+            await ProcessAsync(_recordType, urls.ToArray(), _dnsServer1, _dnsServer2).ConfigureAwait(false);
             IsRunning = false;
+            RunTest.Invoke(() => { RunTest.Enabled = true; });
+        }
+
+        private void SetSearchEngines()
+        {
+            UrlHelper.UseSearchEngineYahoo = checkBox1.Checked;
+            UrlHelper.UseSearchEngineBing = checkBox2.Checked;
+            UrlHelper.UseSearchEngineGoogle = checkBox3.Checked;
+            UrlHelper.UseSearchEngineQwant = checkBox8.Checked;
+            UrlHelper.UseSearchEngineWolfram = checkBox5.Checked;
+            UrlHelper.UseSearchEngineStartPage = checkBox6.Checked;
+            UrlHelper.UseSearchEngineYandex = checkBox7.Checked;
         }
 
         private void SetupView()
@@ -114,16 +124,18 @@ namespace EonaCat.DnsTester
         }
 
         private void AddUrlToView(List<string> urls)
+        {
+            ResultView.Invoke(() =>
             {
                 foreach (var currentUrl in urls)
                 {
-                ListViewItem listURL = new ListViewItem(currentUrl);
+                    var listUrl = new ListViewItem(currentUrl);
-                listURL.SubItems.Add(" ");
+                    listUrl.SubItems.Add(" ");
-                listURL.SubItems.Add(" ");
+                    listUrl.SubItems.Add(" ");
-                listURL.SubItems.Add(" ");
+                    listUrl.SubItems.Add(" ");
-                listURL.SubItems.Add(" ");
+                    listUrl.SubItems.Add(" ");
 
-                ResultView.Items.Add(listURL);
+                    ResultView.Items.Add(listUrl);
                 }
 
                 if (ResultView.Items.Count > 1)
@@ -132,6 +144,7 @@ namespace EonaCat.DnsTester
                 }
 
                 ResultView.Update();
+            });
             Application.DoEvents();
         }
 
@@ -150,13 +163,13 @@ namespace EonaCat.DnsTester
             dnsList2.DisplayMember = "name";
 
             var serverList = Path.Combine(Application.StartupPath, "Servers.xml");
-            DataSet servers1 = new DataSet();
+            var servers1 = new DataSet();
-            DataSet servers2 = new DataSet();
+            var servers2 = new DataSet();
             servers1.ReadXml(serverList);
             servers2.ReadXml(serverList);
 
-            DataTable dataTable1 = servers1.Tables[0];
+            var dataTable1 = servers1.Tables[0];
-            DataTable dataTable2 = servers2.Tables[0];
+            var dataTable2 = servers2.Tables[0];
             dnsList1.DataSource = dataTable1;
             dnsList2.DataSource = dataTable2;
         }
@@ -183,48 +196,46 @@ namespace EonaCat.DnsTester
         }
 
 
-        private async Task Process(DnsRecordType recordType, string[] urls, string dnsAddress1, string dnsAddress2)
+        private async Task ProcessAsync(DnsRecordType recordType, string[] urls, string dnsAddress1, string dnsAddress2)
         {
             if (recordType == 0)
             {
                 recordType = DnsRecordType.A;
             }
 
-            int urlsTotal = urls.Length;
+            var urlsTotal = urls.Length;
             const string dnsId1 = "Dns1";
             const string dnsId2 = "Dns2";
 
             DnsHelper.OnLog -= DnsHelper_OnLog;
             DnsHelper.OnLog += DnsHelper_OnLog;
 
-            for (int i = 0; i < urlsTotal; i++)
+            for (var i = 0; i < urlsTotal; i++)
-            {
-                await Task.Run(async () =>
             {
                 var currentUrl = urls[i];
-
+                await ExecuteDns1Async(recordType, dnsAddress1, currentUrl, dnsId1, i).ConfigureAwait(false);
-                    await ExecuteDns1(recordType, dnsAddress1, currentUrl, dnsId1, i);
+                if (chkDns2.Checked)
-                    if (!chkDns2.Checked) return;
+                {
-                    await ExecuteDns2(recordType, dnsAddress2, currentUrl, dnsId2, i);
+                    await ExecuteDns2Async(recordType, dnsAddress2, currentUrl, dnsId2, i).ConfigureAwait(false);
-                });
+                }
-                await Task.Delay(100);
+                await Task.Delay(100).ConfigureAwait(false);
             }
         }
 
-        private async Task ExecuteDns2(DnsRecordType recordType, string dnsAddress2, string currentUrl, string dnsId2,
+        private async Task ExecuteDns2Async(DnsRecordType recordType, string dnsAddress2, string currentUrl, string dnsId2,
             int i)
         {
             try
             {
                 DnsResponse response2 = null;
-                byte[] queryBytes2 = DnsHelper.CreateDnsQueryPacket(currentUrl, recordType);
+                var queryBytes2 = DnsHelper.CreateDnsQueryPacket(currentUrl, recordType);
-                response2 = await DnsHelper.SendDnsQueryPacket(dnsId2, dnsAddress2, 53, queryBytes2);
+                response2 = await DnsHelper.SendDnsQueryPacketAsync(dnsId2, dnsAddress2, 53, queryBytes2).ConfigureAwait(false);
                 ProcessResponse(response2);
             }
             catch (SocketException socketException)
             {
                 SetStatus(
-                    Convert.ToString(socketException).IndexOf("time", StringComparison.Ordinal) > 0
+                    Convert.ToString(socketException)!.IndexOf("time", StringComparison.Ordinal) > 0
                         ? $"DNS1 Timeout - No response received for {Convert.ToString(DnsHelper.DnsReceiveTimeout / 1000)} seconds"
                         : Convert.ToString(socketException));
             }
@@ -235,7 +246,7 @@ namespace EonaCat.DnsTester
             }
         }
 
-        private async Task ExecuteDns1(DnsRecordType recordType, string dnsAddress1, string currentUrl, string dnsId1,
+        private async Task ExecuteDns1Async(DnsRecordType recordType, string dnsAddress1, string currentUrl, string dnsId1,
             int i)
         {
             if (chkDns1.Checked)
@@ -243,14 +254,14 @@ namespace EonaCat.DnsTester
                 try
                 {
                     DnsResponse response1 = null;
-                    byte[] queryBytes1 = DnsHelper.CreateDnsQueryPacket(currentUrl, recordType);
+                    var queryBytes1 = DnsHelper.CreateDnsQueryPacket(currentUrl, recordType);
-                    response1 = await DnsHelper.SendDnsQueryPacket(dnsId1, dnsAddress1, 53, queryBytes1);
+                    response1 = await DnsHelper.SendDnsQueryPacketAsync(dnsId1, dnsAddress1, 53, queryBytes1).ConfigureAwait(false);
                     ProcessResponse(response1);
                 }
                 catch (SocketException socketException)
                 {
                     SetStatus(
-                        Convert.ToString(socketException).IndexOf("time", StringComparison.Ordinal) > 0
+                        Convert.ToString(socketException)!.IndexOf("time", StringComparison.Ordinal) > 0
                             ? $"DNS1 Timeout - No response received for {Convert.ToString(DnsHelper.DnsReceiveTimeout / 1000)} seconds"
                             : Convert.ToString(socketException));
                 }
@@ -269,7 +280,7 @@ namespace EonaCat.DnsTester
 
         private void ProcessResponse(DnsResponse dnsResponse)
         {
-            if (dnsResponse?.Answers == null || !dnsResponse.Answers.Any())
+            if (dnsResponse == null || dnsResponse?.Answers == null || !dnsResponse.Answers.Any())
             {
                 return;
             }
@@ -286,7 +297,7 @@ namespace EonaCat.DnsTester
 
             ResultView.Invoke(() =>
             {
-                for (int i = 0; i < ResultView.Items.Count; i++)
+                for (var i = 0; i < ResultView.Items.Count; i++)
                 {
                     foreach (var answer in dnsResponse.Answers)
                     {
@@ -298,7 +309,7 @@ namespace EonaCat.DnsTester
                         {
                             case "Dns1":
                                 ResultView.Items[i].SubItems[1].Text =
-                                    Convert.ToString(answer.Data);
+                                    Convert.ToString(answer.Data) ?? string.Empty;
                                 sDeltaTime = Convert.ToString(deltaTime);
                                 ResultView.Items[i].SubItems[2].Text =
                                     sDeltaTime.Length > 5 ? sDeltaTime.Substring(0, 5) : sDeltaTime;
@@ -311,7 +322,7 @@ namespace EonaCat.DnsTester
 
                             case "Dns2":
                                 ResultView.Items[i].SubItems[3].Text =
-                                    Convert.ToString(answer.Data);
+                                    Convert.ToString(answer.Data) ?? string.Empty;
                                 sDeltaTime = Convert.ToString(deltaTime);
                                 ResultView.Items[i].SubItems[4].Text =
                                     sDeltaTime.Length > 5 ? sDeltaTime.Substring(0, 5) : sDeltaTime;
@@ -335,7 +346,7 @@ namespace EonaCat.DnsTester
                 return;
             }
 
-            if (!IPAddress.TryParse(txtResolveIP.Text, out IPAddress iPAddress))
+            if (!IPAddress.TryParse(txtResolveIP.Text, out var iPAddress))
             {
                 MessageBox.Show("Please enter a valid IP address");
                 return;
@@ -355,7 +366,7 @@ namespace EonaCat.DnsTester
                 {
                     MessageBox.Show($"Could not get hostname for IP address '{txtResolveIP.Text}'");
                 }
-            });
+            }).ConfigureAwait(false);
         }
 
         private async void btnResolveHost_Click(object sender, EventArgs e)
@@ -382,7 +393,7 @@ namespace EonaCat.DnsTester
                 {
                     MessageBox.Show($"Could not get IP address for hostname '{txtResolveHost.Text}'");
                 }
-            });
+            }).ConfigureAwait(false);
         }
 
         private void SetStatus(string text)
@@ -419,5 +430,20 @@ namespace EonaCat.DnsTester
         {
             SetUI();
         }
+
+        private void comboBox1_KeyPress(object sender, KeyPressEventArgs e)
+        {
+            e.Handled = true;
+        }
+
+        private void checkBox1_CheckedChanged(object sender, EventArgs e)
+        {
+            UrlHelper.UseSearchEngineYahoo = checkBox1.Checked;
+        }
+
+        private void checkBox2_CheckedChanged(object sender, EventArgs e)
+        {
+            UrlHelper.UseSearchEngineBing = checkBox2.Checked;
+        }
     }
 }

EonaCat.DnsTester/MainForm.resx

@@ -1,4 +1,64 @@
-<root>
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!--
+    Microsoft ResX Schema 
+
+    Version 2.0
+
+    The primary goals of this format is to allow a simple XML format
+    that is mostly human readable. The generation and parsing of the
+    various data types are done through the TypeConverter classes
+    associated with the data types.
+
+    Example:
+
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing"">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+
+    There are any number of "resheader" rows that contain simple
+    name/value pairs.
+
+    Each data row contains a name, and value. The row also contains a
+    type or mimetype. Type corresponds to a .NET class that support
+    text/value conversion through the TypeConverter architecture.
+    Classes that don't support this are serialized and stored with the
+    mimetype set.
+
+    The mimetype is used for serialized objects, and tells the
+    ResXResourceReader how to depersist the object. This is currently not
+    extensible. For a given mimetype the value must be set accordingly:
+
+    Note - application/x-microsoft.net.object.binary.base64 is the format
+    that the ResXResourceWriter will generate, however the reader can
+    read any of the formats listed below.
+
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
   <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
     <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
     <xsd:element name="root" msdata:IsDataSet="true">

EonaCat.DnsTester/Servers.xml

@@ -2,25 +2,30 @@
 <Servers>
 	<!-- My Local Blocky Dns -->
 	<server name="Local Blocky" ip="127.0.0.1"></server>
+	
 	<!-- My External Blocky Dns -->
 	<server name="External Blocky" ip="192.168.1.10"></server>
+	
 	<!-- My Remote Blocky Dns -->
 	<server name="Remote Blocky" ip="192.168.1.254"></server>
-	<!--AdGuard DNS-->
+	
+	<!--AdGuard Dns servers-->
 	<server name="AdGuard Dns (94.140.14.15)" ip="94.140.14.15"></server>
 	<server name="AdGuard Dns (94.140.15.15)" ip="94.140.15.15"></server>
 
-	<!--Verisign-->
-	<server name="Verisign (64.6.64.6)" ip="64.6.64.6"></server>
-	<server name="Verisign (64.6.65.6)" ip="64.6.65.6"></server>
-
-	<!--Google Dns Servers-->
-	<server name="Google (8.8.8.8)" ip="8.8.8.8"></server>
-	<server name="Google (8.8.4.4)" ip="8.8.8.8"></server>
 	<!--CloudFlare Dns servers-->
 	<server name="CloudFlare Standard (1.1.1.1)" ip="1.1.1.1"></server>
 	<server name="CloudFlare Standard (1.0.0.1)" ip="1.0.0.1"></server>
-	<!--Quad9 DNS-->
+
+	<!--Google Dns servers-->
+	<server name="Google (8.8.8.8)" ip="8.8.8.8"></server>
+	<server name="Google (8.8.4.4)" ip="8.8.4.4"></server>
+
+	<!--Quad9 Dns servers-->
 	<server name="Quad9 Dns 1 (9.9.9.9)" ip="9.9.9.9"></server>
 	<server name="Quad9 Dns 2 (149.112.112.9)" ip="149.112.112.9"></server>
+
+	<!--Verisign Dns servers-->
+	<server name="Verisign (64.6.64.6)" ip="64.6.64.6"></server>
+	<server name="Verisign (64.6.65.6)" ip="64.6.65.6"></server>
 </Servers>

README.md

@@ -5,3 +5,9 @@ EonaCat.DnsTester
 Dns Testing tool for Blocky
 
 https://blocky.EonaCat.com
+
+https://www.nuget.org/packages/EonaCat.Blocky
+
+https://www.nuget.org/packages/EonaCat.Dns
+
+[![EonaCat DnsTester](https://github.com/EonaCat/EonaCat.DnsTester/blob/main/Screenshots/1.png?raw=true "EonaCat DnsTester")](https://github.com/EonaCat/EonaCat.DnsTester/blob/main/Screenshots/1.png?raw=true "EonaCat DnsTester")