json data displays in console not in browser – javascript-Collection of common programming errors

I have some json data I retrieve from php code by a jquery $.post() request. The format is json. But the data is not processed on my brower when the callback function is called

$.post(url_send, data_to_send, function(callback_data){
      var info = callback_data.info;
      console.log(callback_data.info);
      ...
});

callback_data = {"success":[{"id":some_number}],"info":"some_string"} 

To debug, I noticed that : if I put in this code console.log(callback_data); the right json data displays in my console, but if I let console.log(callback_data.info), the console displays 'undefined'. Could someone explain that?

Edit : in my php I have $reply = array(‘success’ => $ids,’info’ => $info); echo json_encode($reply);

1. callback_data will be in string format you have to convert it to json using eval to use it as an object.. once you do the eval you should have callback_data.info something like this

   $.post(url_send, data_to_send, function(callback_data){
         callback_data = eval('(' + callback_data + ')');
         console.log(callback_data.info);
         ...
   });
   

2. The json returned by your php page probably doesn’t contain a field named “info”. So, when you try callback_data.info, since there’s no info, it’s undefined.

3. The field is information, it shoud be: callback_data.information

4. There is not attribute in bject named info in ocallback_data but information use information

   Live Demo

   information = callback_data.information
   

Originally posted 2013-11-09 21:17:23.