Ajax with ActiveX WinHTTP 5.1

gistfile1.js

// http://msdn.microsoft.com/en-us/library/aa384273(VS.85).aspx
function test_ajax(){

	var ajax = new ActiveXObject("WinHttp.WinHttpRequest.5.1");
	
	/*	
	// Define the constants used by the option property.
	const WinHttpRequestOption_UserAgentString = 0;    // Name of the user agent
	const WinHttpRequestOption_URL = 1;                // Current URL
	const WinHttpRequestOption_URLCodePage = 2;        // Code page
	const WinHttpRequestOption_EscapePercentInURL = 3; // Convert percents in the URL
	ajax.Option(WinHttpRequestOption_UserAgentString) = 'Mozilla 4.0' ;
	*/
		
	/*
	// HttpRequest SetCredentials flags.
	const HTTPREQUEST_PROXYSETTING_DEFAULT   = 0;
	const HTTPREQUEST_PROXYSETTING_PRECONFIG = 0;
	const HTTPREQUEST_PROXYSETTING_DIRECT    = 1;
	const HTTPREQUEST_PROXYSETTING_PROXY     = 2;
	// Use proxy_server for all requests outside of 
	// the microsoft.com domain.
	ajax.SetProxy( HTTPREQUEST_PROXYSETTING_PROXY, 
	                 "192.168.0.2:65509", 
	                "*.microsoft.com");
	*/
	ajax.Open("GET","http://www.google.com/",true);
	//ajax.SetRequestHeader("User-Agent", "Mozilla");
	ajax.Send();
	try {
		ajax.WaitForResponse();
		return  ajax.ResponseText ;
	}
	catch(err){ 
		alert('Error:' + "\n" + err.message); 
	};
}