function checkAvailabe()
{
//alert('in get data');
var uname=document.register.uname.value
	if(uname!="" && uname.length!=0)
	{
	disab();
	get(uname);
	}
	else
	{
		alert("ادخل اسم المستخدم اولا");	
	}
}

 
 function makePOSTRequest(url, parameters) {
      http_request = false;
      if (window.XMLHttpRequest) { 
         http_request = new XMLHttpRequest();
         if (http_request.overrideMimeType) {
            http_request.overrideMimeType('text/html');
         }
      } else if (window.ActiveXObject) {
         try {
            http_request = new ActiveXObject("Msxml2.XMLHTTP");
         } catch (e) {
            try {
               http_request = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {}
         }
      }
      if (!http_request) {
         alert('Cannot create XMLHTTP instance');
         return false;
      }
      
      http_request.onreadystatechange = alertContents;
      http_request.open('POST', url, true);
      http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
      http_request.setRequestHeader("Content-length", parameters.length);
      http_request.setRequestHeader("Connection", "close");
      http_request.send(parameters);
   }

   function alertContents() {
      if (http_request.readyState == 4) {
         if (http_request.status == 200) {
            //alert(http_request.responseText);
            result = http_request.responseText;
            document.getElementById('check').innerHTML = result;
			document.register.checkbut.disabled= false;
         } else {
            alert('There was a problem with the request.');
         }
      }
   }
   
   
   
   function get(uname) {
      var poststr = "uname=" + encodeURI( uname );
      makePOSTRequest('signUp/checkAvailabe.php', poststr);
   }

function disab()
{
document.register.checkbut.disabled= true;
setInv();		
}