CSharp binding: create Exception class and throw it instead of the default one.

Author: zpgit

Source/buildbindingcsharp.go

@@ -957,7 +957,7 @@ func buildBindingCSharpImplementation(component ComponentDefinition, w LanguageW
 		w.Writeln("        }")
 		w.Writeln("")
 	}
-	w.Writeln("        throw new Exception(sMessage + \"(# \" + errorCode + \")\");")
+	w.Writeln("        throw new ExternalException(sMessage, errorCode);")
 	w.Writeln("      }")
 	w.Writeln("")
 
@@ -1116,6 +1116,10 @@ func buildCSharpExample(componentdefinition ComponentDefinition, w LanguageWrite
 	}
 	w.Writeln("        Console.WriteLine(versionString);")
 	w.Writeln("      }")
+	w.Writeln("      catch (ExternalException ex)")
+	w.Writeln("      {")
+	w.Writeln("        Console.WriteLine(\"Code: \" + ex.ErrorCode + \", Message: \" + ex.Message);")
+	w.Writeln("      }")
 	w.Writeln("      catch (Exception e)")
 	w.Writeln("      {")
 	w.Writeln("        Console.WriteLine(\"Exception: \\\"\" + e.Message + \"\\\"\");")