PHP，print_r($_SESSION) 不显示其内容？
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PHP, print_r($_SESSION) doesn't show its content?
提问by aneuryzm
I want to see the content of the the array $_SESSION with the command print_r($_SESSION) but what I get is just the following output:
我想用命令 print_r($_SESSION) 查看数组 $_SESSION 的内容，但我得到的只是以下输出：
Array ()
what am I missing ?
我错过了什么？
thanks
谢谢
回答by Lizard
Make sure you call session_start()at the top of all the pages you wish to use the session.
确保session_start()在您希望使用会话的所有页面的顶部调用。
http://php.net/manual/en/function.session-start.php
http://php.net/manual/en/function.session-start.php
<?php
session_start();
echo "<pre>";
print_r($_SESSION);
echo "</pre>";
?>
回答by ma?ek
Note<?php session_start(); ?>must be called before any other output is sent to the browser.
Note<?php session_start(); ?>必须在任何其他输出发送到浏览器之前调用。
index.php
索引.php
<?php
session_start();
$_SESSION['hello'] = 'world';
print_r($_SESSION);
?>
Output
输出
Array (
[hello] => world
)
回答by Luis Melgratti
Most likely you are missing.
很可能你失踪了。
session_start();
回答by Hat programmers
Actually Its Printing The Session Variables But You Have Not Set Any Before Therefore The Array Returned By print_r($_SESSION) is Empty Try Setting The Variables First and Then Print Them.
实际上它打印会话变量，但您之前没有设置任何因此print_r（$_SESSION）返回的数组为空尝试先设置变量然后打印它们。
Remember that session_start(); should always be first line.
记住 session_start(); 应该总是第一行。
