Javascript xmlhttprequest asynchoronous call requires alert

[Pallavi R]

In the code below I have to have the alert statement marked by the two *s. Else firefox returns an empty 'temp' even though the 'webtext' is read correctly. How can I remove this requirement?

function getdatalinks(diagnosis,min_age,max_age,gender)
    {    
        var temp="";
        var urii="given URL";
 
        if (window.XMLHttpRequest) 
        {// code for IE7+, Firefox, Chrome, Opera, Safari
        xmlhttp=new XMLHttpRequest();
        } 
        else 
        {// code for IE6, IE5
            xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
        }
 
          xmlhttp.open("GET",urii,true);
        xmlhttp.send(null);
 
          xmlhttp.onreadystatechange=function()
          {//the request is in ready state but not complete
              if(xmlhttp.readyState==4 && xmlhttp.status==200)
              {//request is complete        
                  webtext=String(xmlhttp.responseText);
                alert(webtext);
                temp=webtext;
              }
          };
            alert(temp); //**
            return(temp);
 
    }

[gits]

that is the purpose of a async call. you simply cannot return the value at that point where you do it ... the response is only reliably available in the onreadystatechange-callback. so the flow of your code has to consider that and just can proceed from there. call the next function that you need from inside the callback and you are fine.