JavaScript Forum

**pizza** · 04-16-2007, 04:23 AM

i have an ajax code that works and loads an asp file but since i dont want to deal with asp i want it to get the infrormation from a simle txt file . the code that refers to the asp is this:

Code:

 xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET","some.asp",true);
xmlHttp.send(null);

so if i replace the asp with a simple txt nothing happens, what is the correct way to write the txt?
below is all the code:

Code:

<script type="text/javascript">
function showText(){
xmlHttp=GetXmlHttpObject()
if (xmlHttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  }
 xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET","some.asp",true);
xmlHttp.send(null);
  }
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;
}
function stateChanged() 
{ 
if (xmlHttp.readyState==4)
{ 
document.getElementById("myText").innerHTML=xmlHttp.responseText;
}
} 
  showText();
</script>
</head>
<body>
my text: <div id="myText"></div>  
</body>
</body>
</html>

**JeremyMiller** · 04-16-2007, 11:51 AM

This code is a bit confusing, but let me get you started. Your xmlHttp variable is defined only within functions so it cannot be cross-accessed by functions (it goes out of scope). Instead, declare xmlHttp outside of all functions and then they'll share the variable's values. Next, you have
xmlHttp=GetXmlHttpObject() and within GetXmlHttpObject you start declaring xmlHttp again before returning it at the end. I have no idea what that kind of referencing will result in, but you probably want to try cleaning up the variable names.

That said, let me give you what we use on our site:

Code:

var request = false;
var requested_page = null;

function ajaxSend(url,data,form_type) {
  if (form_type.length == 0) {
    form_type = "GET";
  }
  try {
    request = new XMLHttpRequest();
  } catch (trymicrosoft) {
    try {
      request = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (othermicrosoft) {
      try {
        request = new ActiveXObject("Microsoft.XMLHTTP");
      } catch (failed) {
        request = false;
      }
    }
  }

  if (!request) {
    //Error
  }
  else {
    //ajax commands available.

    if (form_type == "POST") {
      request.open(form_type, url, true);
      request.onreadystatechange = ajaxReceive;
      request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
      request.send(data+"&ajax_call=true");
    }
    else {
      request.open(form_type, url+"?"+data+"&ajax_call=true", true);
      request.onreadystatechange = ajaxReceive;
      request.send(null);
    }
    requested_page = data;
  }
}
function ajaxReceive() {
  if (request.readyState == 4) {
    if (request.status == 200) { //everything went smoothly
      var response = request.responseText;
      receivePage(response);
    }
    // else an error accessing the URL.
  }
  // else still processing, so do not execute routine
}

To use, just call ajaxSend(url,data,form_type). For example, ajaxSend("some.asp","","GET").

Then, declare a function called receivePage that accepts one parameter - the return value - and performs the proper parsing. For example,

Code:

function receivePage(serverResponse) {
  document.getElementById("myText").innerHTML=serverResponse;
}

As a last note, the code I gave you for our site does a bit more than you want but that's because it helps us to be able to determine if a call is ajaxian or not.

Hope this helps!