var xmlHttp;

function checkAvailabilityUsername()
{ 
xmlHttp=GetXmlHttpObject()
if (xmlHttp==null)
 {
 alert ("Browser does not support HTTP Request")
 return
 }

    username=document.getElementById("username").value;
    

var url="ajax/checkUsername.php";
url=url+"?username="+username
url=url+"&sid="+Math.random()
xmlHttp.onreadystatechange=stateChanged7 
xmlHttp.open("GET",url,true)
xmlHttp.send(null)
}


function stateChanged7() 
{ 
if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
 { 
      availability=xmlHttp.responseText ;
  
      
     username=document.getElementById("username").value;
    
      if (trim(username).length ==0)
      {
      document.getElementById("msgboxb").className="messageboxerror";
      document.getElementById("msgboxb").innerHTML="Please enter the username";
	document.getElementById("usernamestatus").value="N";
      }
      else if(availability==1)
      {
      document.getElementById("msgboxb").className="messageboxerror";
      document.getElementById("msgboxb").innerHTML="<b><font color='#ff9900'>The username "+username+" is taken. Please enter another username</font></b>";
	document.getElementById("usernamestatus").value="N";
      }
      else
      {
      document.getElementById("msgboxb").className="messageboxok";
      document.getElementById("msgboxb").innerHTML="<b><font color='#ccff66'>The username "+username+" is available.</font></b>";
	document.getElementById("usernamestatus").value="Y";
      }
     
 } 
}

function GetXmlHttpObject()
{
var xmlHttp=null;
try
 {
 // Firefox, Opera 8.0+, Safari
 xmlHttp=new XMLHttpRequest();
 }
catch (e)
 {
 //Internet Explorer
 try
  {
  xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
  }
 catch (e)
  {
  xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
  }
 }
return xmlHttp;
}