www.kevincornwell.com

AJAX



Comet - High Speed AJAX

Basic Definitions of Comet:
Wiki

Server Technologies:

IE will not allow your to read xmlhttp.responseText untill xmlhttp.readyState = 4 (complete — connection closed). It works in FF.

var http_request = false;  
function makeRequest(url) {
 	http_request = false;
 	if (window.XMLHttpRequest) { // Mozilla, Safari,...
 		http_request = new XMLHttpRequest();
		if (http_request.overrideMimeType) {
 			http_request.overrideMimeType('text/xml');
 			// See note below about this line
 		}
 	} else if (window.ActiveXObject) { // IE
 		try { //
			http_request = new ActiveXObject("Msxml2.XMLHTTP");
        		http_request = new ActiveXObject("Microsoft.XMLHTTP");
 		} catch (e) {
 			try {
 				http_request = new ActiveXObject("Microsoft.XMLHTTP");
 			} catch (e) {} 		}
 	}
 	if (!http_request) {
 		alert('Giving up :( Cannot create an XMLHTTP instance');
 		return false;
 	}
 	http_request.onreadystatechange = alertContents;
 	http_request.open('GET', url, true);
 	http_request.send(null);
  }
  var i = 0; var str = "";
  function alertContents() {
 	$('info').innerHTML = '<h3>'+ Date() + ' ' + http_request.readyState +':</h3>' + http_request.responseText;
 	if (http_request.readyState == 4) {
 		$('info').innerHTML = '<h1>Complete ('+ http_request.status +'):</h1>' + http_request.responseText;
 	}
 }
  function $() {
     var elements = new Array();
     for (var i = 0; i < arguments.length; i++) {
       var element = arguments[i];
       if (typeof element == 'string') {
         if (document.getElementById) {
           element = document.getElementById(element);
         } else if (document.all) {
           element = document.all[element];
         }
       }
       elements.push(element);
     }
     if (arguments.length == 1 && elements.length > 0) {
       return elements[0];
     } else {
       return elements;
     }
 }
function go(){ 	makeRequest('http://www.kevincornwell.com/comet/x-mixed-replace.php'); }

Post Comment Now


Blog | Contact | Gallery | Links | Music | Sandbox | Search | SharePoint | Social Networking | Software | Weather | Web Design


Copyright © 1997-2008 KCSH. All rights reserved.