diff --git a/v2rayN/v2rayN/Base/HttpWebServer.cs b/v2rayN/v2rayN/Base/HttpWebServer.cs
index bbf26c53..9fa72495 100644
--- a/v2rayN/v2rayN/Base/HttpWebServer.cs
+++ b/v2rayN/v2rayN/Base/HttpWebServer.cs
@@ -57,7 +57,7 @@ namespace v2rayN.Base
                     {
                         ThreadPool.QueueUserWorkItem((c) =>
                         {
-                            var ctx = c as HttpListenerContext;
+                            HttpListenerContext ctx = c as HttpListenerContext;
                             try
                             {
                                 string address = ctx.Request.LocalEndPoint.Address.ToString();
diff --git a/v2rayN/v2rayN/Base/HttpWebServerB.cs b/v2rayN/v2rayN/Base/HttpWebServerB.cs
index 59e325dc..403ffedb 100644
--- a/v2rayN/v2rayN/Base/HttpWebServerB.cs
+++ b/v2rayN/v2rayN/Base/HttpWebServerB.cs
@@ -60,19 +60,19 @@ namespace v2rayN.Base
         {
             try
             {
-                var socket = obj as TcpClient;
+                TcpClient socket = obj as TcpClient;
 
-                var inputStream = new BufferedStream(socket.GetStream());
-                var outputStream = new StreamWriter(new BufferedStream(socket.GetStream()));
+                BufferedStream inputStream = new BufferedStream(socket.GetStream());
+                StreamWriter outputStream = new StreamWriter(new BufferedStream(socket.GetStream()));
                 if (inputStream.CanRead)
                 {
-                    var data = ReadStream(inputStream);
+                    string data = ReadStream(inputStream);
 
                     if (data.Contains("/pac/"))
                     {
                         if (_responderMethod != null)
                         {
-                            var address = ((IPEndPoint)socket.Client.LocalEndPoint).Address.ToString();
+                            string address = ((IPEndPoint)socket.Client.LocalEndPoint).Address.ToString();
                             Utils.SaveLog("WebserverB Request " + address);
                             string pac = _responderMethod(address);
 
@@ -122,7 +122,7 @@ namespace v2rayN.Base
 
         private void WriteStream(StreamWriter outputStream, string pac)
         {
-            var content_type = "application/x-ns-proxy-autoconfig";
+            string content_type = "application/x-ns-proxy-autoconfig";
             outputStream.WriteLine("HTTP/1.1 200 OK");
             outputStream.WriteLine(String.Format("Content-Type:{0}", content_type));
             outputStream.WriteLine("Connection: close");
diff --git a/v2rayN/v2rayN/Base/StringEx.cs b/v2rayN/v2rayN/Base/StringEx.cs
index e7f87a44..40544106 100644
--- a/v2rayN/v2rayN/Base/StringEx.cs
+++ b/v2rayN/v2rayN/Base/StringEx.cs
@@ -24,7 +24,7 @@ namespace v2rayN.Base
 
         public static bool IsWhiteSpace(this string value)
         {
-            foreach (var c in value)
+            foreach (char c in value)
             {
                 if (char.IsWhiteSpace(c)) continue;
 
diff --git a/v2rayN/v2rayN/Forms/MainForm.cs b/v2rayN/v2rayN/Forms/MainForm.cs
index 29d72567..9c1d4517 100644
--- a/v2rayN/v2rayN/Forms/MainForm.cs
+++ b/v2rayN/v2rayN/Forms/MainForm.cs
@@ -198,7 +198,7 @@ namespace v2rayN.Forms
                 ListViewItem lvItem = null;
                 if (statistics != null && statistics.Enable)
                 {
-                    var sItem = statistics.Statistic.Find(item_ => item_.itemId == item.getItemId());
+                    ServerStatItem sItem = statistics.Statistic.Find(item_ => item_.itemId == item.getItemId());
                     if (sItem != null)
                     {
                         totalUp = Utils.HumanFy(sItem.totalUp);
@@ -424,7 +424,7 @@ namespace v2rayN.Forms
 
             if (config.vmess[index].configType == (int)EConfigType.Vmess)
             {
-                var fm = new AddServerForm
+                AddServerForm fm = new AddServerForm
                 {
                     EditIndex = index
                 };
@@ -437,7 +437,7 @@ namespace v2rayN.Forms
             }
             else if (config.vmess[index].configType == (int)EConfigType.Shadowsocks)
             {
-                var fm = new AddServer3Form
+                AddServer3Form fm = new AddServer3Form
                 {
                     EditIndex = index
                 };
@@ -449,7 +449,7 @@ namespace v2rayN.Forms
             }
             else if (config.vmess[index].configType == (int)EConfigType.Socks)
             {
-                var fm = new AddServer4Form
+                AddServer4Form fm = new AddServer4Form
                 {
                     EditIndex = index
                 };
@@ -461,7 +461,7 @@ namespace v2rayN.Forms
             }
             else
             {
-                var fm2 = new AddServer2Form
+                AddServer2Form fm2 = new AddServer2Form
                 {
                     EditIndex = index
                 };
@@ -646,7 +646,7 @@ namespace v2rayN.Forms
         {
             GetLvSelectedIndex();
             ClearTestResult();
-            var statistics = new SpeedtestHandler(ref config, ref v2rayHandler, lvSelecteds, actionType, UpdateSpeedtestHandler);
+            SpeedtestHandler statistics = new SpeedtestHandler(ref config, ref v2rayHandler, lvSelecteds, actionType, UpdateSpeedtestHandler);
         }
 
         private void menuExport2ClientConfig_Click(object sender, EventArgs e)
@@ -814,7 +814,7 @@ namespace v2rayN.Forms
 
         private void menuAddShadowsocksServer_Click(object sender, EventArgs e)
         {
-            var fm = new AddServer3Form
+            AddServer3Form fm = new AddServer3Form
             {
                 EditIndex = -1
             };
@@ -829,7 +829,7 @@ namespace v2rayN.Forms
 
         private void menuAddSocksServer_Click(object sender, EventArgs e)
         {
-            var fm = new AddServer4Form
+            AddServer4Form fm = new AddServer4Form
             {
                 EditIndex = -1
             };
@@ -1038,14 +1038,14 @@ namespace v2rayN.Forms
                 List<string[]> datas = new List<string[]>();
                 for (int i = 0; i < config.vmess.Count; i++)
                 {
-                    var index = statistics.FindIndex(item_ => item_.itemId == config.vmess[i].getItemId());
+                    int index = statistics.FindIndex(item_ => item_.itemId == config.vmess[i].getItemId());
                     if (index != -1)
                     {
                         lvServers.Invoke((MethodInvoker)delegate
                         {
                             lvServers.SuspendLayout();
 
-                            var indexStart = 9;
+                            int indexStart = 9;
                             lvServers.Items[i].SubItems[indexStart++].Text = Utils.HumanFy(statistics[index].todayDown);
                             lvServers.Items[i].SubItems[indexStart++].Text = Utils.HumanFy(statistics[index].todayUp);
                             lvServers.Items[i].SubItems[indexStart++].Text = Utils.HumanFy(statistics[index].totalDown);
@@ -1165,7 +1165,7 @@ namespace v2rayN.Forms
 
             for (int k = 0; k < menuSysAgentMode.DropDownItems.Count; k++)
             {
-                var item = ((ToolStripMenuItem)menuSysAgentMode.DropDownItems[k]);
+                ToolStripMenuItem item = ((ToolStripMenuItem)menuSysAgentMode.DropDownItems[k]);
                 item.Checked = (type == k);
             }
 
@@ -1218,8 +1218,8 @@ namespace v2rayN.Forms
 
                         try
                         {
-                            var fileName = Utils.GetPath(downloadHandle.DownloadFileName);
-                            var process = Process.Start("v2rayUpgrade.exe", fileName);
+                            string fileName = Utils.GetPath(downloadHandle.DownloadFileName);
+                            Process process = Process.Start("v2rayUpgrade.exe", fileName);
                             if (process.Id > 0)
                             {
                                 menuExit_Click(null, null);
@@ -1328,7 +1328,7 @@ namespace v2rayN.Forms
                 {
                     if (args.Success)
                     {
-                        var result = args.Msg;
+                        string result = args.Msg;
                         if (Utils.IsNullOrEmpty(result))
                         {
                             return;
@@ -1449,7 +1449,7 @@ namespace v2rayN.Forms
                     if (args.Success)
                     {
                         AppendText(false, $"{hashCode}{UIRes.I18N("MsgGetSubscriptionSuccessfully")}");
-                        var result = Utils.Base64Decode(args.Msg);
+                        string result = Utils.Base64Decode(args.Msg);
                         if (Utils.IsNullOrEmpty(result))
                         {
                             AppendText(false, $"{hashCode}{UIRes.I18N("MsgSubscriptionDecodingFailed")}");
diff --git a/v2rayN/v2rayN/Forms/OptionSettingForm.cs b/v2rayN/v2rayN/Forms/OptionSettingForm.cs
index 5a717b26..8a0000ff 100644
--- a/v2rayN/v2rayN/Forms/OptionSettingForm.cs
+++ b/v2rayN/v2rayN/Forms/OptionSettingForm.cs
@@ -118,7 +118,7 @@ namespace v2rayN.Forms
 
 
 
-            var cbSource = new ComboItem[]
+            ComboItem[] cbSource = new ComboItem[]
             {
                 new ComboItem{ID = (int)Global.StatisticsFreshRate.quick, Text = UIRes.I18N("QuickFresh")},
                 new ComboItem{ID = (int)Global.StatisticsFreshRate.medium, Text = UIRes.I18N("MediumFresh")},
@@ -340,7 +340,7 @@ namespace v2rayN.Forms
 
             config.allowLANConn = chkAllowLANConn.Checked;
 
-            var lastEnableStatistics = config.enableStatistics;
+            bool lastEnableStatistics = config.enableStatistics;
             config.enableStatistics = chkEnableStatistics.Checked;
             config.statisticsFreshRate = (int)cbFreshrate.SelectedValue;
             config.keepOlderDedupl = chkKeepOlderDedupl.Checked;
@@ -390,25 +390,25 @@ namespace v2rayN.Forms
             txtUserblock.Text = Utils.GetEmbedText(Global.CustomRoutingFileName + Global.blockTag);
             cmbroutingMode.SelectedIndex = 3;
 
-            var lstUrl = new List<string>();
+            List<string> lstUrl = new List<string>();
             lstUrl.Add(Global.CustomRoutingListUrl + Global.agentTag);
             lstUrl.Add(Global.CustomRoutingListUrl + Global.directTag);
             lstUrl.Add(Global.CustomRoutingListUrl + Global.blockTag);
 
-            var lstTxt = new List<TextBox>();
+            List<TextBox> lstTxt = new List<TextBox>();
             lstTxt.Add(txtUseragent);
             lstTxt.Add(txtUserdirect);
             lstTxt.Add(txtUserblock);
 
             for (int k = 0; k < lstUrl.Count; k++)
             {
-                var txt = lstTxt[k];
+                TextBox txt = lstTxt[k];
                 DownloadHandle downloadHandle = new DownloadHandle();
                 downloadHandle.UpdateCompleted += (sender2, args) =>
                 {
                     if (args.Success)
                     {
-                        var result = args.Msg;
+                        string result = args.Msg;
                         if (Utils.IsNullOrEmpty(result))
                         {
                             return;
diff --git a/v2rayN/v2rayN/Forms/SubSettingForm.cs b/v2rayN/v2rayN/Forms/SubSettingForm.cs
index 7debf6b1..0cc90ae2 100644
--- a/v2rayN/v2rayN/Forms/SubSettingForm.cs
+++ b/v2rayN/v2rayN/Forms/SubSettingForm.cs
@@ -35,7 +35,7 @@ namespace v2rayN.Forms
 
             for (int k = config.subItem.Count - 1; k >= 0; k--)
             {
-                var item = config.subItem[k];
+                SubItem item = config.subItem[k];
                 if (Utils.IsNullOrEmpty(item.remarks)
                     && Utils.IsNullOrEmpty(item.url))
                 {
@@ -47,7 +47,7 @@ namespace v2rayN.Forms
                 }
             }
 
-            foreach (var item in config.subItem)
+            foreach (SubItem item in config.subItem)
             {
                 SubSettingControl control = new SubSettingControl();
                 control.OnButtonClicked += Control_OnButtonClicked;
@@ -98,7 +98,7 @@ namespace v2rayN.Forms
 
         private void AddSub()
         {
-            var subItem = new SubItem
+            SubItem subItem = new SubItem
             {
                 id = string.Empty,
                 remarks = "remarks",
diff --git a/v2rayN/v2rayN/Handler/ConfigHandler.cs b/v2rayN/v2rayN/Handler/ConfigHandler.cs
index c7c461f8..acb42953 100644
--- a/v2rayN/v2rayN/Handler/ConfigHandler.cs
+++ b/v2rayN/v2rayN/Handler/ConfigHandler.cs
@@ -375,7 +375,7 @@ namespace v2rayN.Handler
                 }
                 else if (vmessItem.configType == (int)EConfigType.Shadowsocks)
                 {
-                    var remark = string.Empty;
+                    string remark = string.Empty;
                     if (!Utils.IsNullOrEmpty(vmessItem.remarks))
                     {
                         remark = "#" + WebUtility.UrlEncode(vmessItem.remarks);
@@ -390,7 +390,7 @@ namespace v2rayN.Handler
                 }
                 else if (vmessItem.configType == (int)EConfigType.Socks)
                 {
-                    var remark = string.Empty;
+                    string remark = string.Empty;
                     if (!Utils.IsNullOrEmpty(vmessItem.remarks))
                     {
                         remark = "#" + WebUtility.UrlEncode(vmessItem.remarks);
@@ -803,7 +803,7 @@ namespace v2rayN.Handler
         public static int AddSubItem(ref Config config, string url)
         {
             //already exists
-            foreach (var sub in config.subItem)
+            foreach (SubItem sub in config.subItem)
             {
                 if (url == sub.url)
                 {
@@ -811,7 +811,7 @@ namespace v2rayN.Handler
                 }
             }
 
-            var subItem = new SubItem
+            SubItem subItem = new SubItem
             {
                 id = string.Empty,
                 remarks = "import sub",
diff --git a/v2rayN/v2rayN/Handler/DownloadHandle.cs b/v2rayN/v2rayN/Handler/DownloadHandle.cs
index d4286a0e..2c76da01 100644
--- a/v2rayN/v2rayN/Handler/DownloadHandle.cs
+++ b/v2rayN/v2rayN/Handler/DownloadHandle.cs
@@ -339,9 +339,9 @@ namespace v2rayN.Handler
             byte[] bytes = Convert.FromBase64String(response);
             string content = Encoding.UTF8.GetString(bytes);
             List<string> valid_lines = new List<string>();
-            using (var sr = new StringReader(content))
+            using (StringReader sr = new StringReader(content))
             {
-                foreach (var line in sr.NonWhiteSpaceLines())
+                foreach (string line in sr.NonWhiteSpaceLines())
                 {
                     if (line.BeginWithAny(IgnoredLineBegins))
                         continue;
diff --git a/v2rayN/v2rayN/Handler/MainFormHandler.cs b/v2rayN/v2rayN/Handler/MainFormHandler.cs
index c4b095b0..c105359a 100644
--- a/v2rayN/v2rayN/Handler/MainFormHandler.cs
+++ b/v2rayN/v2rayN/Handler/MainFormHandler.cs
@@ -38,23 +38,23 @@ namespace v2rayN.Handler
         {
             try
             {
-                var color = ColorTranslator.FromHtml("#3399CC");
-                var index = config.listenerType;
+                Color color = ColorTranslator.FromHtml("#3399CC");
+                int index = config.listenerType;
                 if (index > 0)
                 {
                     color = (new Color[] { Color.Red, Color.Purple, Color.DarkGreen, Color.Orange, Color.DarkSlateBlue, Color.RoyalBlue })[index - 1];
                     //color = ColorTranslator.FromHtml(new string[] { "#CC0066", "#CC6600", "#99CC99", "#666699" }[index - 1]);
                 }
 
-                var width = 128;
-                var height = 128;
+                int width = 128;
+                int height = 128;
 
-                var bitmap = new Bitmap(width, height);
-                var graphics = Graphics.FromImage(bitmap);
-                var drawBrush = new SolidBrush(color);
+                Bitmap bitmap = new Bitmap(width, height);
+                Graphics graphics = Graphics.FromImage(bitmap);
+                SolidBrush drawBrush = new SolidBrush(color);
 
                 graphics.FillEllipse(drawBrush, new Rectangle(0, 0, width, height));
-                var zoom = 16;
+                int zoom = 16;
                 graphics.DrawImage(new Bitmap(Properties.Resources.notify, width - zoom, width - zoom), zoom / 2, zoom / 2);
 
                 Icon createdIcon = Icon.FromHandle(bitmap.GetHicon());
diff --git a/v2rayN/v2rayN/Handler/SpeedtestHandler.cs b/v2rayN/v2rayN/Handler/SpeedtestHandler.cs
index 184307f6..c64d6dab 100644
--- a/v2rayN/v2rayN/Handler/SpeedtestHandler.cs
+++ b/v2rayN/v2rayN/Handler/SpeedtestHandler.cs
@@ -108,7 +108,7 @@ namespace v2rayN.Handler
                 _v2rayHandler.LoadV2ray(_config, _selecteds);
 
                 Thread.Sleep(5000);
-                var httpPort = _config.GetLocalPort("speedtest");
+                int httpPort = _config.GetLocalPort("speedtest");
                 Task[] tasks = new Task[_selecteds.Count];
                 int i = -1;
                 foreach (int itemIndex in _selecteds)
@@ -124,7 +124,7 @@ namespace v2rayN.Handler
                         {
                             WebProxy webProxy = new WebProxy(Global.Loopback, httpPort + itemIndex);
                             int responseTime = -1;
-                            var status = GetRealPingTime(Global.SpeedPingTestUrl, webProxy, out responseTime);
+                            string status = GetRealPingTime(Global.SpeedPingTestUrl, webProxy, out responseTime);
                             string output = Utils.IsNullOrEmpty(status) ? string.Format("{0}ms", responseTime) : string.Format("{0}", status);
                             _updateFunc(itemIndex, output);
                         }
@@ -205,11 +205,11 @@ namespace v2rayN.Handler
                 return -1;
             }
 
-            var httpPort = _config.GetLocalPort("speedtest");
+            int httpPort = _config.GetLocalPort("speedtest");
             index = _selecteds[index];
 
             testCounter++;
-            var webProxy = new WebProxy(Global.Loopback, httpPort + index);
+            WebProxy webProxy = new WebProxy(Global.Loopback, httpPort + index);
             downloadHandle2.DownloadFileAsync(_config, url, webProxy, 20);
 
             return 0;
@@ -217,7 +217,7 @@ namespace v2rayN.Handler
 
         private int GetTcpingTime(string url, int port)
         {
-            var responseTime = -1;
+            int responseTime = -1;
 
             try
             {
@@ -228,10 +228,10 @@ namespace v2rayN.Handler
                     ipAddress = ipHostInfo.AddressList[0];
                 }
 
-                var timer = new Stopwatch();
+                Stopwatch timer = new Stopwatch();
                 timer.Start();
 
-                var endPoint = new IPEndPoint(ipAddress, port);
+                IPEndPoint endPoint = new IPEndPoint(ipAddress, port);
                 Socket clientSocket = new Socket(endPoint.AddressFamily, SocketType.Stream, ProtocolType.Tcp);
 
                 IAsyncResult result = clientSocket.BeginConnect(endPoint, null, null);
@@ -260,7 +260,7 @@ namespace v2rayN.Handler
                 myHttpWebRequest.Timeout = 5000;
                 myHttpWebRequest.Proxy = webProxy;//new WebProxy(Global.Loopback, Global.httpPort);
 
-                var timer = new Stopwatch();
+                Stopwatch timer = new Stopwatch();
                 timer.Start();
 
                 HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();
diff --git a/v2rayN/v2rayN/Handler/StatisticsHandler.cs b/v2rayN/v2rayN/Handler/StatisticsHandler.cs
index 7640faa3..23a41f60 100644
--- a/v2rayN/v2rayN/Handler/StatisticsHandler.cs
+++ b/v2rayN/v2rayN/Handler/StatisticsHandler.cs
@@ -118,8 +118,8 @@ namespace v2rayN.Handler
 
                         if (res != null)
                         {
-                            var itemId = config_.getItemId();
-                            var serverStatItem = GetServerStatItem(itemId);
+                            string itemId = config_.getItemId();
+                            ServerStatItem serverStatItem = GetServerStatItem(itemId);
                             ulong up = 0,
                                  down = 0;
 
@@ -167,8 +167,8 @@ namespace v2rayN.Handler
                     serverStatistics_.server = new List<ServerStatItem>();
                 }
 
-                var ticks = DateTime.Now.Date.Ticks;
-                foreach (var item in serverStatistics_.server)
+                long ticks = DateTime.Now.Date.Ticks;
+                foreach (ServerStatItem item in serverStatistics_.server)
                 {
                     if (item.dateNow != ticks)
                     {
@@ -198,8 +198,8 @@ namespace v2rayN.Handler
 
         private ServerStatItem GetServerStatItem(string itemId)
         {
-            var ticks = DateTime.Now.Date.Ticks;
-            var cur = Statistic.FindIndex(item => item.itemId == itemId);
+            long ticks = DateTime.Now.Date.Ticks;
+            int cur = Statistic.FindIndex(item => item.itemId == itemId);
             if (cur < 0)
             {
                 Statistic.Add(new ServerStatItem
@@ -229,12 +229,12 @@ namespace v2rayN.Handler
             try
             {
 
-                foreach (var stat in source)
+                foreach (Stat stat in source)
                 {
-                    var name = stat.Name;
-                    var value = stat.Value;
-                    var nStr = name.Split(">>>".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
-                    var type = "";
+                    string name = stat.Name;
+                    long value = stat.Value;
+                    string[] nStr = name.Split(">>>".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
+                    string type = "";
 
                     name = name.Trim();
 
@@ -268,7 +268,7 @@ namespace v2rayN.Handler
                 // TCP stack please do me a favor
                 TcpListener l = new TcpListener(IPAddress.Loopback, 0);
                 l.Start();
-                var port = ((IPEndPoint)l.LocalEndpoint).Port;
+                int port = ((IPEndPoint)l.LocalEndpoint).Port;
                 l.Stop();
                 return port;
             }
diff --git a/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs b/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs
index b016947d..b4b629fc 100644
--- a/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs
+++ b/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs
@@ -149,7 +149,7 @@ namespace v2rayN.Handler
         {
             try
             {
-                var inbound = v2rayConfig.inbounds[0];
+                Inbounds inbound = v2rayConfig.inbounds[0];
                 //端口
                 inbound.port = config.inbound[0].localPort;
                 inbound.protocol = config.inbound[0].protocol;
@@ -327,7 +327,7 @@ namespace v2rayN.Handler
         {
             try
             {
-                var outbound = v2rayConfig.outbounds[0];
+                Outbounds outbound = v2rayConfig.outbounds[0];
                 if (config.configType() == (int)EConfigType.Vmess)
                 {
                     VnextItem vnextItem;
@@ -420,7 +420,7 @@ namespace v2rayN.Handler
                     if (!Utils.IsNullOrEmpty(config.security())
                         && !Utils.IsNullOrEmpty(config.id()))
                     {
-                        var socksUsersItem = new SocksUsersItem
+                        SocksUsersItem socksUsersItem = new SocksUsersItem
                         {
                             user = config.security(),
                             pass = config.id(),
@@ -456,7 +456,7 @@ namespace v2rayN.Handler
             {
                 //远程服务器底层传输配置
                 streamSettings.network = config.network();
-                var host = config.requestHost();               
+                string host = config.requestHost();               
                 //if tls
                 if (config.streamSecurity() == Global.StreamSecurity)
                 {
@@ -659,10 +659,10 @@ namespace v2rayN.Handler
         {
             if (config.enableStatistics)
             {
-                var tag = Global.InboundAPITagName;
-                var apiObj = new API();
-                var policyObj = new Policy();
-                var policySystemSetting = new SystemPolicy();
+                string tag = Global.InboundAPITagName;
+                API apiObj = new API();
+                Policy policyObj = new Policy();
+                SystemPolicy policySystemSetting = new SystemPolicy();
 
                 string[] services = { "StatsService" };
 
@@ -679,8 +679,8 @@ namespace v2rayN.Handler
 
                 if (!v2rayConfig.inbounds.Exists(item => { return item.tag == tag; }))
                 {
-                    var apiInbound = new Inbounds();
-                    var apiInboundSettings = new Inboundsettings();
+                    Inbounds apiInbound = new Inbounds();
+                    Inboundsettings apiInboundSettings = new Inboundsettings();
                     apiInbound.tag = tag;
                     apiInbound.listen = Global.Loopback;
                     apiInbound.port = Global.statePort;
@@ -692,7 +692,7 @@ namespace v2rayN.Handler
 
                 if (!v2rayConfig.routing.rules.Exists(item => { return item.outboundTag == tag; }))
                 {
-                    var apiRoutingRule = new RulesItem
+                    RulesItem apiRoutingRule = new RulesItem
                     {
                         inboundTag = new List<string> { tag },
                         outboundTag = tag,
@@ -832,7 +832,7 @@ namespace v2rayN.Handler
         {
             try
             {
-                var inbound = v2rayConfig.inbounds[0];
+                Inbounds inbound = v2rayConfig.inbounds[0];
                 UsersItem usersItem;
                 if (inbound.settings.clients.Count <= 0)
                 {
@@ -921,7 +921,7 @@ namespace v2rayN.Handler
                     return null;
                 }
 
-                var outbound = v2rayConfig.outbounds[0];
+                Outbounds outbound = v2rayConfig.outbounds[0];
                 if (outbound == null
                     || Utils.IsNullOrEmpty(outbound.protocol)
                     || outbound.protocol != "vmess"
@@ -1067,7 +1067,7 @@ namespace v2rayN.Handler
                     return null;
                 }
 
-                var inbound = v2rayConfig.inbounds[0];
+                Inbounds inbound = v2rayConfig.inbounds[0];
                 if (inbound == null
                     || Utils.IsNullOrEmpty(inbound.protocol)
                     || inbound.protocol != "vmess"
@@ -1458,7 +1458,7 @@ namespace v2rayN.Handler
                 dns(configCopy, ref v2rayConfig);
 
 
-                var httpPort = configCopy.GetLocalPort("speedtest");
+                int httpPort = configCopy.GetLocalPort("speedtest");
                 foreach (int index in selecteds)
                 {
                     if (configCopy.vmess[index].configType == (int)EConfigType.Custom)
@@ -1468,7 +1468,7 @@ namespace v2rayN.Handler
 
                     configCopy.index = index;
 
-                    var inbound = new Inbounds
+                    Inbounds inbound = new Inbounds
                     {
                         listen = Global.Loopback,
                         port = httpPort + index,
@@ -1478,12 +1478,12 @@ namespace v2rayN.Handler
                     v2rayConfig.inbounds.Add(inbound);
 
 
-                    var v2rayConfigCopy = Utils.FromJson<V2rayConfig>(result);
+                    V2rayConfig v2rayConfigCopy = Utils.FromJson<V2rayConfig>(result);
                     outbound(configCopy, ref v2rayConfigCopy);
                     v2rayConfigCopy.outbounds[0].tag = Global.agentTag + inbound.port.ToString();
                     v2rayConfig.outbounds.Add(v2rayConfigCopy.outbounds[0]);
 
-                    var rule = new RulesItem
+                    RulesItem rule = new RulesItem
                     {
                         inboundTag = new List<string> { inbound.tag },
                         outboundTag = v2rayConfigCopy.outbounds[0].tag,
diff --git a/v2rayN/v2rayN/Handler/V2rayHandler.cs b/v2rayN/v2rayN/Handler/V2rayHandler.cs
index 61d59bf6..5eeb411a 100644
--- a/v2rayN/v2rayN/Handler/V2rayHandler.cs
+++ b/v2rayN/v2rayN/Handler/V2rayHandler.cs
@@ -104,7 +104,7 @@ namespace v2rayN.Handler
                         Process[] existing = Process.GetProcessesByName(vName);
                         foreach (Process p in existing)
                         {
-                            var path = p.MainModule.FileName;
+                            string path = p.MainModule.FileName;
                             if (path == $"{Utils.GetPath(vName)}.exe")
                             {
                                 KillProcess(p);
diff --git a/v2rayN/v2rayN/HttpProxyHandler/HttpProxyHandle.cs b/v2rayN/v2rayN/HttpProxyHandler/HttpProxyHandle.cs
index 897b4f03..4e0a0e29 100644
--- a/v2rayN/v2rayN/HttpProxyHandler/HttpProxyHandle.cs
+++ b/v2rayN/v2rayN/HttpProxyHandler/HttpProxyHandle.cs
@@ -23,7 +23,7 @@ namespace v2rayN.HttpProxyHandler
             {
                 if (type != 0)
                 {
-                    var port = Global.httpPort;
+                    int port = Global.httpPort;
                     if (port <= 0)
                     {
                         return false;
diff --git a/v2rayN/v2rayN/HttpProxyHandler/PACServerHandle.cs b/v2rayN/v2rayN/HttpProxyHandler/PACServerHandle.cs
index 7b47fc4f..16f4cfef 100644
--- a/v2rayN/v2rayN/HttpProxyHandler/PACServerHandle.cs
+++ b/v2rayN/v2rayN/HttpProxyHandler/PACServerHandle.cs
@@ -114,7 +114,7 @@ namespace v2rayN.HttpProxyHandler
         {
             try
             {
-                var pac = GetPacList(address);
+                string pac = GetPacList(address);
                 return pac;
             }
             catch (Exception ex)
@@ -165,7 +165,7 @@ namespace v2rayN.HttpProxyHandler
 
         private static string GetPacList(string address)
         {
-            var port = Global.httpPort;
+            int port = Global.httpPort;
             if (port <= 0)
             {
                 return "No port";
@@ -174,22 +174,22 @@ namespace v2rayN.HttpProxyHandler
             {
                 List<string> lstProxy = new List<string>();
                 lstProxy.Add(string.Format("PROXY {0}:{1};", address, port));
-                var proxy = string.Join("", lstProxy.ToArray());
+                string proxy = string.Join("", lstProxy.ToArray());
 
                 string strPacfile = Utils.GetPath(Global.pacFILE);
                 if (!File.Exists(strPacfile))
                 {
                     FileManager.UncompressFile(strPacfile, Resources.pac_txt);
                 }
-                var pac = File.ReadAllText(strPacfile, Encoding.UTF8);
+                string pac = File.ReadAllText(strPacfile, Encoding.UTF8);
                 pac = pac.Replace("__PROXY__", proxy);
 
                 if (_config.userPacRule.Count > 0)
                 {
-                    var keyWords = "var rules = [";
+                    string keyWords = "var rules = [";
                     if (pac.IndexOf(keyWords) >= 0)
                     {
-                        var userPac = string.Join($"\",{Environment.NewLine}\"", _config.userPacRule.ToArray());
+                        string userPac = string.Join($"\",{Environment.NewLine}\"", _config.userPacRule.ToArray());
                         userPac = string.Format("\"{0}\",", userPac);
                         pac = pac.Replace(keyWords, keyWords + userPac);
                     }
diff --git a/v2rayN/v2rayN/HttpProxyHandler/PrivoxyHandler.cs b/v2rayN/v2rayN/HttpProxyHandler/PrivoxyHandler.cs
index 773bad53..f738a318 100644
--- a/v2rayN/v2rayN/HttpProxyHandler/PrivoxyHandler.cs
+++ b/v2rayN/v2rayN/HttpProxyHandler/PrivoxyHandler.cs
@@ -172,7 +172,7 @@ namespace v2rayN.HttpProxyHandler
                 /*
                  * Under PortableMode, we could identify it by the path of v2ray_privoxy.exe.
                  */
-                var path = process.MainModule.FileName;
+                string path = process.MainModule.FileName;
 
                 return Utils.GetTempPath($"{_privoxyName}.exe").Equals(path);
 
diff --git a/v2rayN/v2rayN/HttpProxyHandler/SysProxyHandle.cs b/v2rayN/v2rayN/HttpProxyHandler/SysProxyHandle.cs
index e79e5a4d..00c91c14 100644
--- a/v2rayN/v2rayN/HttpProxyHandler/SysProxyHandle.cs
+++ b/v2rayN/v2rayN/HttpProxyHandler/SysProxyHandle.cs
@@ -69,10 +69,10 @@ namespace v2rayN.HttpProxyHandler
             else
             {
                 // restore user settings
-                var flags = _userSettings.Flags;
-                var proxy_server = _userSettings.ProxyServer ?? "-";
-                var bypass_list = _userSettings.BypassList ?? "-";
-                var pac_url = _userSettings.PacUrl ?? "-";
+                string flags = _userSettings.Flags;
+                string proxy_server = _userSettings.ProxyServer ?? "-";
+                string bypass_list = _userSettings.BypassList ?? "-";
+                string pac_url = _userSettings.PacUrl ?? "-";
                 arguments = $"set {flags} {proxy_server} {bypass_list} {pac_url}";
 
                 // have to get new settings
@@ -110,7 +110,7 @@ namespace v2rayN.HttpProxyHandler
             using (AutoResetEvent outputWaitHandle = new AutoResetEvent(false))
             using (AutoResetEvent errorWaitHandle = new AutoResetEvent(false))
             {
-                using (var process = new Process())
+                using (Process process = new Process())
                 {
                     // Configure the process using the StartInfo properties.
                     process.StartInfo.FileName = Utils.GetTempPath("sysproxy.exe");
@@ -167,10 +167,10 @@ namespace v2rayN.HttpProxyHandler
                         // log the arguments
                         throw new Exception(process.StartInfo.Arguments);
                     }
-                    var stderr = error.ToString();
-                    var stdout = output.ToString();
+                    string stderr = error.ToString();
+                    string stdout = output.ToString();
 
-                    var exitCode = process.ExitCode;
+                    int exitCode = process.ExitCode;
                     if (exitCode != (int)RET_ERRORS.RET_NO_ERROR)
                     {
                         throw new Exception(stderr);
diff --git a/v2rayN/v2rayN/Mode/Config.cs b/v2rayN/v2rayN/Mode/Config.cs
index 0674a3f0..4e962fb2 100644
--- a/v2rayN/v2rayN/Mode/Config.cs
+++ b/v2rayN/v2rayN/Mode/Config.cs
@@ -427,7 +427,7 @@ namespace v2rayN.Mode
 
         public string getItemId()
         {
-            var itemId = $"{address}{port}{requestHost}{path}";
+            string itemId = $"{address}{port}{requestHost}{path}";
             itemId = Utils.Base64Encode(itemId);
             return itemId;
         }
diff --git a/v2rayN/v2rayN/Program.cs b/v2rayN/v2rayN/Program.cs
index c67bb345..3d57be50 100644
--- a/v2rayN/v2rayN/Program.cs
+++ b/v2rayN/v2rayN/Program.cs
@@ -112,7 +112,7 @@ namespace v2rayN
 
         static bool UnzipLibs()
         {
-            var fileName = Utils.GetPath("libs.zip");
+            string fileName = Utils.GetPath("libs.zip");
             if (!FileManager.ByteArrayToFile(fileName, Resources.libs))
             {
                 return false;
diff --git a/v2rayN/v2rayN/Tool/FileManager.cs b/v2rayN/v2rayN/Tool/FileManager.cs
index 4bfc0830..bd5ebf93 100644
--- a/v2rayN/v2rayN/Tool/FileManager.cs
+++ b/v2rayN/v2rayN/Tool/FileManager.cs
@@ -11,7 +11,7 @@ namespace v2rayN.Tool
         {
             try
             {
-                using (var fs = new FileStream(fileName, FileMode.Create, FileAccess.Write))
+                using (FileStream fs = new FileStream(fileName, FileMode.Create, FileAccess.Write))
                     fs.Write(content, 0, content.Length);
                 return true;
             }
@@ -31,8 +31,8 @@ namespace v2rayN.Tool
                 byte[] buffer = new byte[4096];
                 int n;
 
-                using (var fs = File.Create(fileName))
-                using (var input = new GZipStream(new MemoryStream(content),
+                using (FileStream fs = File.Create(fileName))
+                using (GZipStream input = new GZipStream(new MemoryStream(content),
                         CompressionMode.Decompress, false))
                 {
                     while ((n = input.Read(buffer, 0, buffer.Length)) > 0)
@@ -56,8 +56,8 @@ namespace v2rayN.Tool
         {
             try
             {
-                using (var fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
-                using (var sr = new StreamReader(fs, encoding))
+                using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
+                using (StreamReader sr = new StreamReader(fs, encoding))
                 {
                     return sr.ReadToEnd();
                 }
diff --git a/v2rayN/v2rayN/Tool/Job.cs b/v2rayN/v2rayN/Tool/Job.cs
index daee62cf..66bfb128 100644
--- a/v2rayN/v2rayN/Tool/Job.cs
+++ b/v2rayN/v2rayN/Tool/Job.cs
@@ -16,13 +16,13 @@ namespace v2rayN
         public Job()
         {
             handle = CreateJobObject(IntPtr.Zero, null);
-            var extendedInfoPtr = IntPtr.Zero;
-            var info = new JOBOBJECT_BASIC_LIMIT_INFORMATION
+            IntPtr extendedInfoPtr = IntPtr.Zero;
+            JOBOBJECT_BASIC_LIMIT_INFORMATION info = new JOBOBJECT_BASIC_LIMIT_INFORMATION
             {
                 LimitFlags = 0x2000
             };
 
-            var extendedInfo = new JOBOBJECT_EXTENDED_LIMIT_INFORMATION
+            JOBOBJECT_EXTENDED_LIMIT_INFORMATION extendedInfo = new JOBOBJECT_EXTENDED_LIMIT_INFORMATION
             {
                 BasicLimitInformation = info
             };
@@ -50,7 +50,7 @@ namespace v2rayN
 
         public bool AddProcess(IntPtr processHandle)
         {
-            var succ = AssignProcessToJobObject(handle, processHandle);
+            bool succ = AssignProcessToJobObject(handle, processHandle);
 
             if (!succ)
             {
diff --git a/v2rayN/v2rayN/Tool/UIRes.cs b/v2rayN/v2rayN/Tool/UIRes.cs
index a6b455a9..f0660435 100644
--- a/v2rayN/v2rayN/Tool/UIRes.cs
+++ b/v2rayN/v2rayN/Tool/UIRes.cs
@@ -10,7 +10,7 @@ namespace v2rayN
 
         static string LoadString(ResourceManager resMgr, string key)
         {
-            var value = resMgr.GetString(key);
+            string value = resMgr.GetString(key);
             if (value == null)
             {
                 throw new KeyNotFoundException($"key: {key}");
diff --git a/v2rayN/v2rayN/Tool/Utils.cs b/v2rayN/v2rayN/Tool/Utils.cs
index 49474bad..c4fc5acc 100644
--- a/v2rayN/v2rayN/Tool/Utils.cs
+++ b/v2rayN/v2rayN/Tool/Utils.cs
@@ -39,7 +39,7 @@ namespace v2rayN
 
             try
             {
-                var assembly = Assembly.GetExecutingAssembly();
+                Assembly assembly = Assembly.GetExecutingAssembly();
                 using (Stream stream = assembly.GetManifestResourceStream(res))
                 using (StreamReader reader = new StreamReader(stream))
                 {
@@ -194,7 +194,7 @@ namespace v2rayN
         {
             try
             {
-                var plainTextBytes = System.Text.Encoding.UTF8.GetBytes(plainText);
+                byte[] plainTextBytes = System.Text.Encoding.UTF8.GetBytes(plainText);
                 return Convert.ToBase64String(plainTextBytes);
             }
             catch (Exception ex)
@@ -272,20 +272,20 @@ namespace v2rayN
         /// <param name="unit">单位</param>
         public static void ToHumanReadable(ulong amount, out double result, out string unit)
         {
-            var factor = 1024u;
-            var KBs = amount / factor;
+            uint factor = 1024u;
+            ulong KBs = amount / factor;
             if (KBs > 0)
             {
                 // multi KB
-                var MBs = KBs / factor;
+                ulong MBs = KBs / factor;
                 if (MBs > 0)
                 {
                     // multi MB
-                    var GBs = MBs / factor;
+                    ulong GBs = MBs / factor;
                     if (GBs > 0)
                     {
                         // multi GB
-                        var TBs = GBs / factor;
+                        ulong TBs = GBs / factor;
                         if (TBs > 0)
                         {
                             // 你是魔鬼吗？ 用这么多流量
@@ -322,7 +322,7 @@ namespace v2rayN
 
         public static void DedupServerList(List<Mode.VmessItem> source, out List<Mode.VmessItem> result, bool keepOlder)
         {
-            var list = new List<Mode.VmessItem>();
+            List<Mode.VmessItem> list = new List<Mode.VmessItem>();
             if (!keepOlder) source.Reverse(); // Remove the early items first
 
             bool _isAdded(Mode.VmessItem o, Mode.VmessItem n)
@@ -341,7 +341,7 @@ namespace v2rayN
                     o.streamSecurity == n.streamSecurity;
                 // skip (will remove) different remarks
             }
-            foreach (var item in source)
+            foreach (Mode.VmessItem item in source)
             {
                 if (!list.Exists(i => _isAdded(i, item)))
                 {
@@ -410,7 +410,7 @@ namespace v2rayN
             //可能是CIDR
             if (ip.IndexOf(@"/") > 0)
             {
-                var cidr = ip.Split('/');
+                string[] cidr = ip.Split('/');
                 if (cidr.Length == 2)
                 {
                     if (!IsNumberic(cidr[0]))
@@ -515,7 +515,7 @@ namespace v2rayN
         {
             try
             {
-                var value = RegReadValue(autoRunRegPath, autoRunName, "");
+                string value = RegReadValue(autoRunRegPath, autoRunName, "");
                 string exePath = GetExePath();
                 if (value?.Equals(exePath) == true)
                 {
@@ -917,10 +917,10 @@ namespace v2rayN
                                                 GraphicsUnit.Pixel);
                             }
 
-                            var source = new BitmapLuminanceSource(target);
-                            var bitmap = new BinaryBitmap(new HybridBinarizer(source));
+                            BitmapLuminanceSource source = new BitmapLuminanceSource(target);
+                            BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
                             QRCodeReader reader = new QRCodeReader();
-                            var result = reader.decode(bitmap);
+                            Result result = reader.decode(bitmap);
                             if (result != null)
                             {
                                 ret = result.Text;
diff --git a/v2rayN/v2rayUpgrade/MainForm.cs b/v2rayN/v2rayUpgrade/MainForm.cs
index 64982a12..1bc22b7f 100644
--- a/v2rayN/v2rayUpgrade/MainForm.cs
+++ b/v2rayN/v2rayUpgrade/MainForm.cs
@@ -35,7 +35,7 @@ namespace v2rayUpgrade
                 Process[] existing = Process.GetProcessesByName("v2rayN");
                 foreach (Process p in existing)
                 {
-                    var path = p.MainModule.FileName;
+                    string path = p.MainModule.FileName;
                     if (path == GetPath("v2rayN.exe"))
                     {
                         p.Kill();
@@ -49,7 +49,7 @@ namespace v2rayUpgrade
                 return;
             }
 
-            var fileName = GetPath(_tempFileName);
+            string fileName = GetPath(_tempFileName);
             try
             {
                 File.Delete(fileName);
@@ -60,7 +60,7 @@ namespace v2rayUpgrade
                     return;
                 }
 
-                var startKey = "v2rayN/";
+                string startKey = "v2rayN/";
 
                 using (ZipArchive archive = ZipFile.OpenRead(fileName))
                 {
@@ -70,7 +70,7 @@ namespace v2rayUpgrade
                         {
                             continue;
                         }
-                        var fullName = entry.FullName;
+                        string fullName = entry.FullName;
                         if (fullName.StartsWith(startKey))
                         {
                             fullName = fullName.Substring(startKey.Length, fullName.Length - startKey.Length);