php - 如何在 Codeigniter 中按页码取消设置 session 数据最多 n 页？

Question

$this->session->unset_userdata('current_page_'.$pagenumber);

通过使用此代码，我正在为每个页码从 session 中取消设置数据，但问题是在某些时候我不知道 session 中存在多少页数据，例如:

$this->session->unset_userdata('current_page_'.1);
$this->session->unset_userdata('current_page_'.2);
$this->session->unset_userdata('current_page_'.3);
$this->session->unset_userdata('current_page_'.4);
.
.
.
$this->session->unset_userdata('current_page_'.?????);

是否有任何方法可以取消设置 session 中的数据，其中键为“current_page_%” 提前致谢。

Answer 1

您可以尝试搜索 session 的首字母(即current_page_)并相应地取消设置。

<?php
function startsWith($haystack, $needle) {
    // search backwards starting from haystack length characters from the end
    return $needle === "" || strrpos($haystack, $needle, -strlen($haystack)) !== FALSE;
}

foreach($this->session->all_userdata() as $key => $value)
{
    if(startsWith($key, 'current_page_'))
        $this->session->unset_userdata($key);
}

例如:

<?php
function startsWith($haystack, $needle) {
    // search backwards starting from haystack length characters from the end
    return $needle === "" || strrpos($haystack, $needle, -strlen($haystack)) !== FALSE;
}

$session = array(
            'current_page_12' => 'abc', 
            'current_page_qw1' => 'xyz', 
            'hello' => 'world', 
            'current_page_23d' => 'mno', 
            'example' => '112'
        );

foreach($session as $key => $value)
{
    if(startsWith($key, 'current_page_'))
        unset($session[$key]);
}

print_r($session);

输出:

Array
(
    [hello] => world
    [example] => 112
)

演示:
http://3v4l.org/uh4HK