How to pass string from C# to PHP web page using PHP nusoap server

I have problem regrading C# to PHP communication. I have read many old posts here and after that i came to conclusion that i have to Use PHP SOAP Web service on server side to get interaction with c#.

Here is the code which i tried:
//webservice.php

<?php
require_once 'lib/nusoap.php';
require_once 'notify.php';
$server=new nusoap_server();
$server->configureWSDL('webservice', 'urn:webservice');
$server->register('getMessage',array('msg'=>'xsd:string'),array('return'=>'xsd:null'));
$HTTP_RAW_POST_DATA = isset($HTTP_RAW_POST_DATA)? $HTTP_RAW_POST_DATA : '';
$server->service($HTTP_RAW_POST_DATA);
?>

//notify.php which containing function which is registered with webservice

<?php
$message="temp";
function getMessage($msg)
{
  $message=$msg;
}
?>

//member.php getting message and displaying it. This will be message i want from C# code when ever i //click the button.

<?php
require_once 'notify.php';
echo $message;
?>

In 2nd part in Visual Studio 2012 i added web service reference of WSDL file correctly, and written following code for a button.

//c# code

       private void button1_Click(object sender, EventArgs e)
       {
           localhost.webservice src = new localhost.webservice();
           src.getMessage("Hello");
       }

But when ever i click button and i saw member.php page nothing happens.???
Still it showing “temp”. I want this “Hello” should be shown whenever i click button.
Any help please?? I am worried wasted my whole week to learn this and now have limited time for my project. I shall be very thankful to you.

Regards,