add host and port overload for new channel
diff --git a/src/csharp/Grpc.Examples.MathClient/MathClient.cs b/src/csharp/Grpc.Examples.MathClient/MathClient.cs
index 85d9cdc..360fe92 100644
--- a/src/csharp/Grpc.Examples.MathClient/MathClient.cs
+++ b/src/csharp/Grpc.Examples.MathClient/MathClient.cs
@@ -41,7 +41,7 @@
         {
             GrpcEnvironment.Initialize();
 
-            using (Channel channel = new Channel("127.0.0.1:23456"))
+            using (Channel channel = new Channel("127.0.0.1", 23456))
             {
                 Math.IMathClient stub = new Math.MathClient(channel);
                 MathExamples.DivExample(stub);