Majid Fouladpour Majid Fouladpour - 1 year ago 83
PHP Question

'At' symbol before variable name in PHP: @$_POST

I've seen function calls preceded with an at symbol to switch off warnings. Today I was skimming some code and found this:

$hn = @$_POST['hn'];

What good will it do here?

Answer Source

The @ is the error suppression operator in PHP.

PHP supports one error control operator: the at sign (@). When prepended to an expression in PHP, any error messages that might be generated by that expression will be ignored.



In your example, it is used before the variable name to avoid the E_NOTICE error there. If in the $_POST array, the hn key is not set; it will throw an E_NOTICE message, but @ is used there to avoid that E_NOTICE.

Note that you can also put this line on top of your script to avoid an E_NOTICE error:

error_reporting(E_ALL ^ E_NOTICE);

PHP 6 Note:

Because @ operator is very slow, it won't work on ini_set eg @ini_set.

You should avoid using it where you can.