what is error suppressor in php

The error suppressor in php is @, and the @ operator is only valid for expressions. When we place it before a PHP expression, any error messages that may be generated by the expression will be ignored, using methods such as: [$value = @$cache[$key];].

#PHP supports an error control operator: @. When placed before a PHP expression, any error message that expression may produce is ignored.

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If you use set_error_handler() to set a custom error handling function, it will still be called, but this error The handler function can (and should) call error_reporting(), which will return 0 if there is @ before the error statement.

Example:

<?php
/* Intentional file error */
$my_file = @file (&#39;non_existent_file&#39;) or
    die ("Failed opening file: error was &#39;$php_errormsg&#39;");

// this works for any expression, not just functions:
$value = @$cache[$key];
// will not issue a notice if the index $key doesn&#39;t exist.

?>

@ Operator is only valid for expressions.

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A simple rule for novices is: if you can get a value from somewhere, you can add it in front of it on the @ operator. For example, you can put it before variables, function and include calls, constants, etc. It cannot be placed before the definition of a function or class, nor can it be used in conditional structures such as if and foreach.

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