[Modify] Polish it

websocket-sharp/Net/HttpUtility.cs

@@ -612,11 +612,12 @@ namespace WebSocketSharp.Net
 
     internal static Encoding GetEncoding (string contentType)
     {
-      var parts = contentType.Split (';');
+      foreach (var elm in contentType.Split (';')) {
-      foreach (var p in parts) {
+        var part = elm.Trim ();
-        var part = p.Trim ();
+        if (part.IndexOf ("charset", StringComparison.OrdinalIgnoreCase) != 0)
-        if (part.StartsWith ("charset", StringComparison.OrdinalIgnoreCase))
+          continue;
-          return Encoding.GetEncoding (part.GetValue ('=', true));
+
+        return Encoding.GetEncoding (part.GetValue ('=', true));
       }
 
       return null;