php 注意：未定义索引：登录 C:\xampp\htdocs\index.php 第 55 行
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php Notice: Undefined index: login in C:\xampp\htdocs\index.php on line 55
提问by Cocoa Dev
Possible Duplicate:
PHP: “Notice: Undefined variable” and “Notice: Undefined index”
I am getting warnings. I would like to take care of it. Here is the offending code
我收到警告。我想照顾它。这是违规代码
if ($_REQUEST['login']) $user = $_REQUEST['login'];
elseif ($_COOKIE['user']) $user = $_COOKIE['user'];
if ($_REQUEST['encpas']) $pass = $_REQUEST['encpas'];
elseif ($_COOKIE['pass']) $pass = $_COOKIE['pass'];
if ($_REQUEST['randsess']) $sess = $_REQUEST['randsess'];
elseif ($_COOKIE['sess']) $sess= $_COOKIE['sess'];
I am not sure how to get rid of them.
我不知道如何摆脱它们。
Thanks
谢谢
回答by Zoltan Toth
Check your variables to see if they set and have a value or not:
检查您的变量以查看它们是否设置并具有值：
if ( isset($_REQUEST['login']) ) {
$user = $_REQUEST['login'];
} elseif ( isset($_COOKIE['user']) ) {
$user = $_COOKIE['user'];
}
回答by Abraham Brookes
Try using isset() to check if the index has been initialized before you check if it's true or not. http://au.php.net/manual/en/function.isset.php
尝试使用 isset() 检查索引是否已初始化，然后再检查它是否为真。 http://au.php.net/manual/en/function.isset.php
回答by JorgeeFG
You should use array_key_exists, or isset. The last is faster according to some benchmarks.
您应该使用 array_key_exists 或 isset。根据一些基准，最后一个更快。
if( isset( $_REQUEST['login'] ) ) {
$user = $_REQUEST['login'];
}
isset doesn't count NULL as value.
isset 不将 NULL 计为值。
Be careful with this because the following:
小心这一点，因为以下几点：
index.php?login=&otherstuff
Will set login with empty value. But it will be set.
将登录设置为空值。但它会被设置。
