php json_encode returning null

Question

Array
(
    [sEcho] => 1
    [iTotalRecords] => 7521
    [iTotalDisplayRecords] => 1
    [aaData] => Array
        (
            [0] => Array
                 


        

Answer 1

Actually it doesn't return null, http://codepad.org/A34KdUf5.

Maybe your PHP version doesn't support json_encode().