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HomeBackend DevelopmentPHP TutorialThe function of PHP @ at mark, the function of phpat mark_PHP tutorial

The function of PHP @ at mark, the function of phpat mark

Looking at the PHP code, there are always @ symbols in front of some lines, and I never know what it means. For example dede5.7 @$ni=imagecreatetruecolor($ftoW,$ftoH);

I used it today, so just remember it. In fact, it is an error control character, that is, even if an error occurs, the error message will be ignored and the following code will continue to be executed.

@<span>$page</span>=<span>$_GET</span>['page']?<span>intval</span>(<span>$_GET</span>['page']):1;

This sentence is to get the value of the page keyword from the URL, such as "index.php?page=5", then $page will get 5.

But if there is an error, for example, there is no page keyword after "index.php", and if $_GET['page'] does not exist, an error will be reported. At this time, you can ignore this small error with @.

Another example:

<span>$conn</span> = mysqli_conncet("q","w","e","r");

This will input error information about connecting to the database.

If you add @ in front of $conn, you can prevent it from outputting error messages.

@<span>$conn</span> = mysqli_conncet("q","w","e","r");

Just jot it down here.

The effect of adding & after php function [at]

For reference.

[php]Why are some functions preceded by @(at)

Do not output any error message to the page when the function is executed.

For example, if you use
require(DISCUZ_ROOT.'./forumdata/cache/cache_settings.php');
if the cache_settings.php file cannot be found, an error will be reported
. But if you add @, you won’t get an error

www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/890824.htmlTechArticlePHP @ at mark function, phpat mark function. Look at the PHP code, there are always @ symbols in front of some lines, always Don't know what it means. For example dede5.7 @$ni=imagecreatetruecolor($ftoW,$ftoH)...
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