Why are integers becoming strings when I POST using jquery.ajax to a PHP script

Question

I have spent the last hour attempting to figure this out to no avail. There are many posts on SO about jQuery and ajax(), but I haven't been able to find one that deals with my specific issue.

The basics of my code:

On the client:

var data = {"id": 1};
j.ajax({
  type: "POST",
  url: "postTestingResult.php",
  data: {'data': data},
  dataType: "json",
  success: ajaxSuccess,
  error: ajaxError
});

On the server using PHP:

$data = $_POST['data'];
echo $data; //{"id": "1"}

Why is the integer value becoming a string? How do I prevent this? I really don't want to have to create a custom function to loop through my data object (which in reality is quite complex) to convert all the values.

Many thanks!

Answer 1

When parameters are sent through $_GET or $_POST , They are interpreted as strings.

You may need to cast them appropriately to make them suit how it works for you.

Answer 2

In your case, you need to json_decode the data you received. Then you will have variables in their the type you sent via Ajax.

$data = json_decode($_POST['data'], true);
// $data['id'] is now int

$_POST['data'] is a string as explained in other answers, but when you decode it you can inner elements get their proper types.