Question

I have checked the return string is “added” or “used” or “false”, but every time it do the last statement which is document.write(theresult). What is the problem, i am expecting if the return string is “used” then alert “1”. Please help, many thanks.

function add_member()
    {
    var xmlhttp;

    if (window.XMLHttpRequest)
      {// code for IE7+, Firefox, Chrome, Opera, Safari
      xmlhttp=new XMLHttpRequest();
      }
    else
      {// code for IE6, IE5
      xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
      }
    xmlhttp.onreadystatechange=function()
      {
      if (xmlhttp.readyState==4 && xmlhttp.status==200)
        {
       // document.getElementById("txtHint").innerHTML=xmlhttp.responseText;
      var theresult = xmlhttp.responseText;

            if (theresult == "used") { 
            alert("1");
            }

            else if (theresult == "added") { 
            alert("2");
            }

            else if (theresult == "false") { 
            alert("3");
            }

            else
             { 
            document.write(theresult);
            }



        }
      }
xmlhttp.open("GET","add.php?addnew=true&email=" + document.memberform.email.value + "&tel=" + document.memberform.tel.value,true);
xmlhttp.send();
}

Answer 1

@JBL Ajax response text is not a plain string even though you set a string to it. You cannot compare it. If you want to pass a string and compare, do it in response header.