Explain syntax of

Question

I'm following a PHP/AJAX tutorial on form validation. (I'm new to php!).

Could someone explain the syntax of this line:

<?=@$_REQUEST['username']?>

The context is the value attribute of an input field.

I know how $_REQUEST works. I just don't get the <?=@ part. I understand <? can be used in lieu of <?php (but isn't always supported!) and <?=$variable?> is special syntax for echoing variables. What does the @ symbol do?

Thanks.

Links:

Form validation tutorial

Explanation for special syntax

`` is a PHP shorttag, adding the equalsign `=` is a sort of shortcut for echo, so the result is outputted. — adeneo, Nov 19 '13 at 18:41
And BTW, that's horrible code. Never write something like this. — deceze, Nov 19 '13 at 18:44
I concur, this information can be found in: [this question](http://stackoverflow.com/questions/3737139/reference-what-does-this-symbol-mean-in-php) Though Amal's answer is more concise, detailed and does not require venturing elsewhere. — Patrick Borkowicz, Nov 19 '13 at 19:09

score 6 · Accepted Answer · answered Nov 19 '13 at 18:41

<?= ?> is the short echo syntax. <?=$var?> is equivalent to <?php echo $var; ?>.

From the PHP manual:

echo also has a shortcut syntax, where you can immediately follow the opening tag with an equals sign. Prior to PHP 5.4.0, this short syntax only works with the short_open_tag configuration setting enabled.

@ is the error suppression operator. When prepended to an expression in PHP, any error messages that might be generated by that expression will be ignored.

In short, <?=@$_REQUEST['username']?> will try to print out the value of $_REQUEST['username'] (without ouputting any errors). It's not a good practice and shouldn't be used in your code. If you don't want to display the errors, turn off display_errors in your php.ini configuration and log them instead.

Or better yet, check if the var is set before echoing. – AbraCadaver Nov 19 '13 at 18:52 — AbraCadaver, Nov 19 '13 at 18:52

Explain syntax of

1 Answers1