What is the error control operator in php

The error control operator in php is "@". If you place it before a PHP expression, any error information that may be generated by the expression will be ignored. The "@" operator is only valid for expressions. It can be placed before variables, functions, include calls, constants, etc., but cannot be placed before the definition of a function or class.

The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer

php error control operation Symbol: @

#PHP supports the use of the error control operator @. Place it before a PHP expression and any error messages the expression may produce will be ignored.

If a custom error handling function is set with set_error_handler(), this error handling function will still be called, and if @ is used before the error statement, the error handling function will return 0.

It should be noted that the @ operator is only valid for expressions. Simply put, if you can get a value from somewhere, you can add the @ operator in front of it. For example, the @ operator can be used before variables, functions, include calls, constants, etc., but it cannot be placed before the definition of a function or class, nor can it be used before conditional structures such as if and foreach statements. The

@ operator is also effective for serious errors that can cause the program to terminate. This means that if @ is used to suppress the error message before a function call that does not exist or has the wrong letter, the program will Die there without any hint.

[Example] Use the @ error control operator to mask errors in the code.

<?php
    $link = @mysqli_connect("127.0.0.1", "my_user", "my_password", "my_db") or die(&#39;数据库连接失败！&#39;);
?>

The running results are as follows:

数据库连接失败！

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