Problem parsing XML output (PHP/JQuery)

Question

I scratch my head in frustration, but I can't find the answer. I'm new to Ajax and I'm trying this easy script:

Here's my code:

JAVASCRIPT:

$(document).ready(function(){    
 $("#toggle_album").click(function () {  
  $.post('backend/load_album_thumbnails.php', {  
      text: 'my string',  
          number: 23  
  }, function(xml) {  
          var timestamp = $(xml).find("time").text();
          alert(xml);
          alert(timestamp);
  });  
 });
});

the alert(xml) returns:

     <? xml version="1.0"?>
<response status="ok">
<time>23:33:13</time>
<string>my string</string>
</response>

the alert(timestamp) returns empty

i have also tried:

timestamp = $("time",xml).text();

with the same result.

I added the extra space in the xml start tag because it dissapeared here on stackoverflow. The only reason for this error I can think of is that the return data isn't in XML format, but I can't figure out why that would be the case.

Appreciate any answers.

Answer 1

You're correct, the reason it's not working is that the return data isn't in XML format. Generally, if a web server doesn't return a text/xml Content-Type header, then certain browsers (and therefore jQuery) won't bother parsing the XML.

To get it to work, your options are:

1. Modify your response headers to specify XML format using PHP's header() function and then, change your response so that it uses well-formed XML. The code to do this would look something like:

   header('Content-Type: text/xml; charset=UTF-8');
   echo "<?xml version=\"1.0\"?>
   <response status="ok">
     <time>$timestamp</time>
     <string>$mystring</string>
   </response>";
   

2. Change the way you handle the response in your JavaScript code (for example, write a simple regular expression parser, although this is considered bad for your health)

3. Change your response to something like JSON so that you can use jQuery's $.getJSON() method to send the request and parse the response to a JavaScript object (PHP has some very nice built-in JSON functions).