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What is the meaning of @ file_exists preceded by @ symbol in php

2025-02-24 Update From: SLTechnology News&Howtos shulou NAV: SLTechnology News&Howtos > Development >

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This article mainly introduces the meaning of @ file_exists preceded by @ symbol in php. It has certain reference value, and interested friends can refer to it. I hope you will gain a lot after reading this article. Let's take you to know it.

In PHP, the @ symbol before "@ file_exists" means "error control operator"; the error control operator is used to control the error output, shielding the error message from the expression after the operator from being displayed, and not really solving the error.

This article operating environment: Windows10 system, PHP7.1 version, Dell G3 computer.

What does @ mean by adding @ before @ file_exists in php

@ is the error control operator in the PHP operator.

Add the @ symbol before the file_exists function to disable the output of the error message of this function, so that the information is output only by the program when the file does not exist.

First of all, let's take a look at what error control operators do.

As the name implies, the error control operator is used to control the error output. This control only shields the error message from display, not really solves the error.

The method used is as simple as adding "@" before the wrong expression.

Often when you use some functions in a program, you can use this operator to mask unnecessary error messages, as long as the error message does not affect the operation of the program. If there are some errors that affect the operation of the program, we do not recommend using error control characters, which is not conducive to eliminating errors in the program.

It is important to note that our "@" error control character cannot be placed before the definition of a function or class, nor can it be used in conditional structures and so on. The "@" control is valid only for expressions.

To put it simply: if we get a value from one place, we can put @ in front of it. For example, put @ before variables, constants, and function calls.

Let's take a look at an example of the use of the error control operator when we open a file that doesn't exist, masking it with "@".

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