Generic Ajax Request

Here's a generic way to create an AJAX request (AJAX code below being JavaScript):

function createRequest(){
 
 request=null;
 
 try{
  request = new XMLHttpRequest();
 }catch(tryMS){
  try{
   request = new ActiveXObject("Mxsml2.XMLHTTP");
  }catch(otherMS){
   try{
    request = new ActiveXObject("Microsoft.XMLHTTP");
   }catch(failed){
    request=null;
   }
  }
 }
 
 return request;
}

And a sample function that uses it:

function getPage(){
 
 try{
  
  request = createRequest();
 
  var url ="/some/page.html";
  
  request.open("GET", url, true);
 
  request.onreadystatechange=displayPage;
 
  request.send(null);
 
 }catch(e){
  alert(e)
 }
 
}


function displayPage(){
 try{
  if (request.readyState== 4){
   obj = document.getElementById('someDiv');
   if (request.status== 200){
    obj.innerHTML = request.responseText;
   }
  }
 }catch(e){
  alert(e + request.responseText);
 }
} 

Next on the reading list:

Ajax Security