用explode然后计算数组元素个数?
在直接的函数吗?
回复讨论(解决方案)
mb_substr_count
$s = '判断一个字符串中是否存在两个或以上的子字符串';if(preg_match('/(.+).*\\1/u', $s)) echo 'yes';//看看都匹配到了什么preg_match_all('/(.+).*\\1/u', $s, $r);print_r($r);yes
Array
(
[0] => Array
(
[0] => 个字符串中是否存在两个
)
[1] => Array
(
[0] => 个
)
)
注意:gbk 不可这么写!
虽然去掉 u 修饰符后可用于 gbk,但结果并不准确
已解决,谢谢楼上两位版主。

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Setting the httponly flag is crucial for session cookies because it can effectively prevent XSS attacks and protect user session information. Specifically, 1) the httponly flag prevents JavaScript from accessing cookies, 2) the flag can be set through setcookies and make_response in PHP and Flask, 3) Although it cannot be prevented from all attacks, it should be part of the overall security policy.

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TostartaPHPsession,usesession_start()atthescript'sbeginning.1)Placeitbeforeanyoutputtosetthesessioncookie.2)Usesessionsforuserdatalikeloginstatusorshoppingcarts.3)RegeneratesessionIDstopreventfixationattacks.4)Considerusingadatabaseforsessionstoragei

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mPDF
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