var xmlhttp;

var curForm;
var curDescription;
var curValue;
var curField;


function GetXmlHttpObject()
{	
	if (window.XMLHttpRequest)
	{
		// code for IE7+, Firefox, Chrome, Opera, Safari		
		
		return new XMLHttpRequest();		
	}
	if (window.ActiveXObject)
	{
		// code for IE6, IE5		
		return new ActiveXObject("Microsoft.XMLHTTP");
	}
	return null;
}

function valueExists(form, entity, parameter, description, value, field)
{
	xmlhttp = GetXmlHttpObject();
	if (xmlhttp == null)
	{
		// send information without verifying
		form.submit();
	}
	
	if (value != "")
	{
		var url = "exists.php?e= " + entity;
		url += "&p=" + escape(parameter) + "&v=" + escape(value);
		
		curForm = form;
		curDescription = description;
		curValue = value;
		curField = field;
		
		xmlhttp.onreadystatechange = exists;
		
		xmlhttp.open("GET",url,true);
		xmlhttp.send(null);
	}
	
}

function exists()
{
	if (xmlhttp.readyState == 4)
	{		
		var responseValue = xmlhttp.responseText;		
		
		//document.getElementById("errorDinMsg").style.visibility = "";
		
		if (responseValue == "0")
		{		
			//alert(curDescription + " " + curValue + " already exists.");
			//document.getElementById(curField).focus();			
			document.getElementById("errorDinMsg").innerHTML = curDescription + " " + curValue + " already exists.<br/>";			
			//location.href = "#errorMessageAnchor";
		}
		else if (responseValue == "1")
			document.getElementById("errorDinMsg").innerHTML = "";
		/*else
		{			
			alert("An unespecified error occurred");
		}*/
	}
}