var xmlHttp = null;
function createXMLHttpRequest()
    {          
        var num = "0"; 
        if(window.ActiveXObject)
        {
            num = "1";
            try
            {
            num = "2";
                xmlHttp = new ActiveXObject('MSXML2.XMLHTTP.4.0');
                    
            }
            catch(e)
            {
                try
                {
                num = "3";
                    xmlHttp = new ActiveXObject('MSXML2.XMLHTTP.3.0');
                    
                }
                catch(e)
                {
                    try
                    {
                     num = "4";
                        xmlHttp = new ActiveXObject('MSXML2.XMLHTTP.2.6');
                       
                    }
                    catch(e)
                    {
                        try
                        {
                        num = "5";
                            xmlHttp = new ActiveXObject('MSXML2.XMLHTTP');
                            
                        }
                        catch(e)
                        {
                            try
                            {
                            num = "6";
                                xmlHttp = new ActiveXObject('Microsoft.XMLHTTP');
                                
                            }
                            catch(e)
                            {
                                alert(num);
                            }
                        }
                    }
                }
            }
        }
        else if(window.XMLHttpRequest)
        {
            xmlHttp=new XMLHttpRequest();
        }
    }