Ajax not working

[MDanz]

where did i go wrong? It should update mysql(insertsuscribe function) and change the image in the anchor tag.  This is my first time doing AJAX, what did i do wrong?

 

php

$id= $row['id'];

echo "<div class='suscribe'><a id='s$id' href='javascript:suscribe($id);'><img src='/suscribe.jpg' alt='suscribe' /></a></div>";

 

ajax

function suscribe(number)
{
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("s"+number).innerHTML="<img src='/unsuscribe.jpg' alt='unsuscribe' />";
    }
  }
xmlhttp.open("GET","suscribe.php?id="+number,true);
xmlhttp.send();
}

 

suscribe.php

<?php  session_start();  
include "database.php";

$id = $_GET['id'];

$database = new Database();
$database->opendb();
$database->insertsuscribe($id);
$database->closedb();
   
?>

[MDanz]

i've simplified it.

 

This should be simple.  I click on the subscribe.jpg image and the image changes to unsubscribe.jpg. and then subscribe.php is called.  But nothing is happening when i click the subscribe image??

 

echo "<a id='s1' href='javascript:subscribe(1)'><img src='/subscribe.jpg' alt='subscribe' /></a>";

function subscribe(number)

{
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("s"+number).innerHTML="<img src='/unsubscribe.jpg' alt='unsubscribe' />";
    }
  }
xmlhttp.open("GET","subscribe.php?id="+number,true);
xmlhttp.send();
}

[trq]

You should read this.

[MDanz]

so i should never use JavaScript with AJAX? always jQuery and AJAX?  I was following a tutorial, is their a specific reason?

[trq]

I was following a tutorial, is their a specific reason?

 

You could write your own Ajax functionality in JavaScript (as you have done), but it is much better to use tried and true implementations that are well tested, flexible and easy to use. Using a framework for JavaScript just takes allot of the grunt work out of it.