On my client side I'm sending an ajax request with jQuery in the following matter:

$.post(script.php, { "var1":"something", "var2":"[1,2,3]" }, function(data) { }, "json");

On the server side, in the CodeIgniter's controller I'm receiving the values like so:

$var1 = trim($this->input->post('var1'));
$var2 = trim($this->input->post('var2'));

My question is how do I convert the string in $var2 into a PHP array. I tried using json_decode($var2, true) but it returns a null since "[1,2,3]" is not a legal JSON string by itself.

Also, if you believe there is a better way for me to read the values on the server-side please show me how.

Thank you.