var ObjIndex = 0;
function JsUser(ContainerID) {
    this.ContainerID = ContainerID;
    JsUser.prototype.ObjArray.push(this);
    this.ObjIndex = JsUser.prototype.ObjArray.length - 1;
}

JsUser.prototype.ObjArray = new Array();
JsUser.prototype.GetResponse = function(xUrl, ResponseHandler) {
    var xmlhttp = false;
    /*@cc_on@*/
    /*@if (@_jscript_version >= 5)
    // JScript gives us Conditional compilation, we can cope with old IE versions.
    // and security blocked creation of the objects.
    try {
        xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
    }
    catch (e) {
        try {
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }
        catch (E) {
            xmlhttp = false;
        }
    }
    /*@end@*/

    if (!xmlhttp && typeof XMLHttpRequest != 'undefined') {
        xmlhttp = new XMLHttpRequest();
    }
    xmlhttp.open("GET", xUrl, true);
    xmlhttp.onreadystatechange = function() {
        if (xmlhttp.readyState == 4) {
            ResponseHandler(xmlhttp.responseXML.documentElement, this);
        }
    }
    xmlhttp.send(null)
}

JsUser.prototype.HandleResponse = function(DocumentElement, CurObj) {
    var HTMLData = DocumentElement.childNodes[0].childNodes[0].nodeValue;

    if (HTMLData.toString().toLowerCase() == "true") {
        HTMLData = "<font color='green'>This ID is available.</font>"
    }
    else {
        HTMLData = "<font color='red'>This ID is not available.</font>"
    }
    document.getElementById(JsUser.prototype.ObjArray[ObjIndex].ContainerID).innerHTML = HTMLData;
}

JsUser.prototype.CheckAvailability = function(UserName) {
    ObjIndex = this.ObjIndex;
    this.GetResponse("AjaxCheckAvailability.axd?UN=" + UserName, this.HandleResponse);
   
}