var AjaxAvailability = Class.create();

AjaxAvailability.prototype = {
	initialize: function() {	
		$('txt_User').onblur = function() { 
			var flag = false;
			if ($('Regularexpressionvalidator1')!=null)
				flag = $('Regularexpressionvalidator1').style.visibility != "hidden";
			ApplymentBox.request($('txt_User').value, flag); return false; 
		}
	},
	request: function(user, flagInvalid)	{
		if(user != '' && !flagInvalid)
		{
			var url    = 'CRUD_Users.aspx';
			var pars   = 'User=' + user + '&NONCACHE=' + Math.random() + '&AjaxAction=CheckAvailability';
			$('lbl_Availability').update('');
			var ajaxApplyment = new Ajax.Request(url, {method: 'GET', postBody: true, onComplete: this.handleResponse, onFailure: this.reportError, parameters: pars});
		}
		else
		{
			$('lbl_Availability').update('');
		}
	},
	handleResponse: function(req) {
		var _responseArray   = req.responseText;
		$('lbl_Availability').update(req.responseText);
	},
	reportError: function(req) {
	} 
}

function init_AjaxAvailability() { 
	ApplymentBox = new AjaxAvailability(); 
}

Event.observe(window, 'load', init_AjaxAvailability, false);