PHP & JSON – Fatal error: Cannot use object of type stdClass as array

When working with JSON and PHP, things can get a bit tricky. One such situation might be decoding JSON data, which probably occurs more often than not in a web application.

Fatal Error ...

I came across this fatal php error:

Fatal error: Cannot use object of type stdClass as array…

The cause was a json_decode call that I thought was entirely innocent.

Apparently, some genious thought it was a great idea to make the return value of the json_decode function be an object. It turns out that you have to explicitly state that you want an array.

$raw = json_decode($json); // bad way
echo( $raw["somekey"] ); // fatal error ...

$better = json_decode($json, true);
echo( $raw["somekey"] ); // no error!

According to the PHP.net documentation on json_decode, you need to set the second assoc argument to true so that PHP will return arrays.

That’s all there is to this silly error.