อยากจะถามว่า โค๊ด ajax ทำไม window.locationในโค๊ดของ ajax มันไม่ทำงานค่ะ คือมันไม่ ทำการ redirect ไปหน้าที่ต้องการค่ะช่วยดูให้หน่อยนะค่ะ


<script language="JavaScript">
    var HttPRequest = false;

    function doCallAjax() {
    HttPRequest = false;
    if (window.XMLHttpRequest) { // Mozilla, Safari,...
    HttPRequest = new XMLHttpRequest();
    if (HttPRequest.overrideMimeType) {
    HttPRequest.overrideMimeType('text/html');
    }
    } else if (window .ActiveXObject) { // IE
    try {
    HttPRequest = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
    try {
       HttPRequest = new ActiveXObject("Microsoft.XMLHTTP");
    } catch (e) {}
    }
    }
   
    if (!HttPRequest) {
    alert('Cannot create XMLHTTP instance');
    return false;
    }
 
    var url = 'logincheck.php';
    var pmeters = "tUsername=" + encodeURI( document.getElementById("txtUsername").value) +
      "&tPassword=" + encodeURI( document.getElementById("txtPassword").value );

   HttPRequest.open('POST',url,true);

   HttPRequest.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
   HttPRequest.setRequestHeader("Content-length", pmeters.length);
   HttPRequest.setRequestHeader("Connection", "close");
   HttPRequest.send(pmeters);
   
   
   HttPRequest.onreadystatechange = function()
   {

    if(HttPRequest.readyState == 3)  // Loading Request
    {
     document.getElementById("mySpan").innerHTML = "Now is Loading...";
    }

    if(HttPRequest.readyState == 4) // Return Request
    {
     if(HttPRequest.responseText == 'Y')
     {
     
      

     window.location.href = "edit.php";
     }
     else
     {
      document.getElementById("mySpan").innerHTML = HttPRequest.responseText;
     }
    }
    
   }

    }
 </script>