var page = "system/check_username.php";
var target = "user_check";
function checkUsername(url,getstr,target)
{

    // native XMLHttpRequest object
   document.getElementById(target).innerHTML = 'Loading...';
   if (window.XMLHttpRequest) {
       req = new XMLHttpRequest();
       req.onreadystatechange = function() {usrCheckDone(target);};
       req.open("POST", url + "?getstr=" + getstr, true);
       req.send(null);

   // IE/Windows ActiveX version
   } else if (window.ActiveXObject) {
       req = new ActiveXObject("Microsoft.XMLHTTP");
       if (req) {
           req.onreadystatechange = function() {usrCheckDone(target);};
           req.open("POST", url + "?getstr=" + getstr, true);
           req.send();
       }
   }
         //setTimeout("ajax(page,'user_check')", 20000);
}

function usrCheckDone(target) {
   // only if req is "loaded"
   if (req.readyState == 4) {
       // only if "OK"
       if (req.status == 200 || req.status == 304) {
           results = req.responseText;
           document.getElementById(target).innerHTML = results;
       } else {
           document.getElementById(target).innerHTML="ajax error:\n" +
               req.statusText;
       }
   }
}


/*
 * Error checking
 */
function validateField(fType, fID, fValue) {
	if ( fType == 'username' ) {
		//alert('Ehlo'+fID+fValue);
		/*
		$(document).ready(function(){
			$('#username').removeClass("input");
			$("#username").addClass("error_msg");
			alert('test');
			document.getElementById('username').style.borderWidth = "1px";
			document.getElementById('username').style.borderStyle = "solid";
			document.getElementById('username').style.borderColor = "red";
		});
		*/
	}
}