PHP Operator (7) "Error Control Operator" Example Explanation

Today I will explain to you the "Error Control Operator" in PHP operators.

First of all, let’s understand ErrorWhat does the control operator do?

The error control operator, as its name implies, is used to control error output. This control only blocks the error information and prevents it from being displayed. It does not really solve the error.

The method is very simple, just add "@" before the wrong expression.

When unnecessary error messages often appear when using certain functions in a program, you can use this operator to shield them, provided that the error message does not affect the running of the program. If there are some errors that affect program operation, we do not recommend using error control characters, as this is not conducive to eliminating program errors.

There is something to note here. Our "@" error control character cannot be placed before the definition of a function or class, nor can it be used in conditional structures, etc. The "@" control character is only valid for expressions. To put it simply: if we get a value from a place, we can put @ in front of it. For example, put @ in front of variables, constants, and function calls.

Let’s take a look at Usage examples of error control operators

When we open a file that does not exist, use "@" to block the output of error messages

When "@" is not used;

<?php
$open_file = fopen("index.php","r");
?>

will have the following output:

The above is a warning error message, roughly It means prompting us that the file "index.php" does not exist. The error message is in the third line...

However, when we use "@", this error message will not appear. Implementation The code is as follows.

<?php

$open_file = @fopen("index.php","r");

?>

In this way, we will not have an error message output. Of course, the error still exists, but it is not visible.

The above example is our response to "@". Simple application of error control operators. In the next section, we will introduce the ternary operator in PHP operators in detail. Recommended articles:

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PHP Operator (1) "Arithmetic Operator" Example Explanation

2.

PHP Operator (2) "String Operator" Example Detailed Example

3.

PHP Operator (3) "Assignment Operator" Example Example

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PHP Operator (4) "Bit Operator" Example Example

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PHP Operator (5) "Logical Operator" Examples

6.

PHP Operator (6) "Comparison Operator" Example explanation

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