function ajax_createXMLHttp()
{
    var ret = null;
    try {
        ret = new ActiveXObject('Msxml2.XMLHTTP');
    }
    catch (e) {
        try {
            ret = new ActiveXObject('Microsoft.XMLHTTP');
        }
        catch (ee) {
            ret = null;
        }
    }
    if (!ret && typeof XMLHttpRequest != 'undefined')
        ret = new XMLHttpRequest();

    return ret;
}

function ajax_getFile(url,methode,params){
	ajax= new ajax_createXMLHttp();
	if(methode=='get'){
		ajax.open('get',url,false);
		ajax.send(null);
	}
	else{
		 ajax.open('post',url,false);
		 ajax.setRequestHeader( "Content-type" , "application/x-www-form-urlencoded" );
         ajax.send(params);
	}
	return ajax.responseText;
}