Calling a server method from script function

.cs file
[ScriptMethod, WebMethod]
 
   public static string CallingserverMethod(string name)
   {
       return "Hi" + name + Environment.NewLine + "This is an example";
   }
 

.aspx file
 
<script type="text/javascript">
      function servermethod()
      {
          PageMethods.CallingserverMethod(onSuccess, onFailure);
      }
 
  function onSuccess(result) {
          alert(result);
      }
 

      function onFailure(error) {
          alert(error);
      } 
 
</script>