Question

I am using the $.post() method to retrieve a json formatted string which looks like this:

{elementid:10},{elementid:11},{elementid:12},{elementid:14},{elementid:15}

In the success callback function of $.post(), I would like to loop the values of this json formatted string but I can’t figure out how to do it.

  // data returns {elementid:10},{elementid:11},{elementid:12},{elementid:14}, etc.

  $.post('form.php',

        {'postvalues' : input_ids},

        function(data){

              var elements = Array();

              elements = [data];

              for(var i=0; i<elements.length; i++) {
                    var value = elements[i]['elementid'];
                    alert('value = '+value);
              }
  });

When I do this, instead of getting value = 10, value = 11, value = 12, etc. in the alert box,
I get value = undefined

What must I change in the format of the variable ‘data’ so that it will be interpreted as array values and not a string?

thanks for your help

Answer 1

Your string isn’t valid JSON if you don’t have the '[' and ']' characters.

You can add those in , then parse it using the jQuery.parseJSON()^[docs] method.

elements = jQuery.parseJSON( '[' + data + ']' );

…but it would be better if you sent correct JSON data from the server.

Also, your JSON keys must be wrapped in double quotes.

{"elementid":10},{"elementid":11},{"elementid":12},{"elementid":14},{"elementid":15}