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In PHP, you can use the unset() function and the predefined variable "$_SESSION" to clear the specified session, the syntax is "unset($_SESSION['session name']);".
The operating environment of this tutorial: windows7 system, PHP7.1 version, DELL G3 computer
In php, clearing the specified session means deleting it $_SESSION
The specified element of the array;
Simply put, clearing the specified session is the same as the operation of the array. Simply log out of an element of the $_SESSION
array.
For example, when deleting $_SESSION['name']
, you can use the unset() function directly, such as unset($_SESSION['name'])
; .
The unset() function can release the specified variable. Its syntax format is as follows:
unset(mixed $var [, mixed $...])
where $var is the variable to be released. The unset() function can receive multiple parameters. Between the parameters Use,separate.
Note: When using the unset() function to delete a single Session element, be careful not to omit the specific element name, that is, do not unregister the entire $_SESSION array at once, as this may cause accidental Unexpected errors.
[Example] Use the unset() function to delete the specified Session element.
<?php session_start(); echo '<pre class="brush:php;toolbar:false">'; $str = 'PHP中文网'; $arr = ['删除 Session','$_SESSION']; $_SESSION['name'] = $str; $_SESSION['url'] = 'https://www.php.cn/'; $_SESSION['title'] = $arr; echo '定义一个 Session,如下所示:<br>'; print_r($_SESSION); echo '删除 Session 中名为 title 的元素:<br>'; unset($_SESSION['title']); print_r($_SESSION); ?>
The running results are as follows:
定义一个 Session,如下所示: Array ( [name] => PHP中文网 [url] => https://www.php.cn/ [title] => Array ( [0] => 删除 Session [1] => $_SESSION ) ) 删除 Session 中名为 title 的元素: Array ( [name] => PHP中文网 [url] => https://www.php.cn/ )
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