我将如何测试是否使用 php 设置了 cookie，如果未设置，则什么也不做
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How would I test if a cookie is set using php and if it's not set do nothing
提问by Aaron
I've tried
我试过了
$cookie = $_COOKIE['cookie'];
if the cookie is not set it will give me an error
如果 cookie 没有设置它会给我一个错误
PHP ERROR
Undefined index: cookie
How would I prevent it from giving me an empty variable>
我将如何防止它给我一个空变量>
回答by Rocket Hazmat
回答by John Parker
You can use array_key_existsfor this purpose as follows:
为此，您可以使用array_key_exists，如下所示：
$cookie = array_key_exists('cookie', $_COOKIE) ? $_COOKIE['cookie'] : null;
回答by Shoe
Depending on your needs.
取决于您的需求。
// If not set, $cookie = NULL;
if (isset($_COOKIE['cookie'])) { $cookie = $_COOKIE['cookie']; }
or
或者
// If not set, $cookie = '';
$cookie = (isset($_COOKIE['cookie'])) ? $_COOKIE['cookie'] : '';
or
或者
// If not set, $cookie = false;
$cookie = (isset($_COOKIE['cookie'])) ? $_COOKIE['cookie'] : false;
References:
参考：
回答by Naftali aka Neal
Try this:
尝试这个：
$cookie = isset($_COOKIE['cookie'])?$_COOKIE['cookie']:'';
//checks if there is a cookie, if not then an empty string
回答by Mike Q
Example not mentioned in responses: Say you set a cookie for 60 seconds if conditions are right :
回复中未提及的示例：假设条件合适，您将 cookie 设置为 60 秒：
if ($some_condition == $met_condition) {
setcookie('cookie', 'some_value', time()+ 60, "/","", false);
}
Technically we need to check that it's set AND it's not expired or it will throw warnings etc.. :
从技术上讲，我们需要检查它是否已设置且未过期，否则会引发警告等。：
$cookie = ''; //or null if you prefer
if (array_key_exists('cookie', $_COOKIE) && isset($_COOKIE['cookie'])) {
$cookie = $_COOKIE['cookie'];
}
You would want to check in a way that ensures that expired cookies aren't used and it's set, the above example could obviously not always set the cookie etc.. We should always account for that. The array_key_exists is mainly their to keep warnings from showing up in logs but it would work without it.
您可能希望以一种确保不使用和设置过期 cookie 的方式进行检查，上面的示例显然不能总是设置 cookie 等。我们应该始终考虑到这一点。array_key_exists 主要是为了防止警告显示在日志中，但没有它也可以工作。
