php 注意：未定义变量：第 9 行“”中的 _SESSION
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Notice: Undefined variable: _SESSION in "" on line 9
提问by user2203600
Here is my php code:
这是我的php代码：
<?php include("inc/incfiles/header.inc.php")?>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Member Index</title>
<link href="css/main.css" rel="stylesheet" type="text/css" />
</head>
<body>
<h1>Welcome <?php echo ($_SESSION['SESS_fname']);?></h1>
<a href="member-profile.php">My Profile</a> | <a href="logout.php">Logout</a>
<p>This is a password protected area only accessible to members. </p>
</body>
</html>
I know something I wrong with the code but I don't know how to fix it. My error says: "Notice: Undefined variable: _SESSION in C:\xampp\htdocs\Smasher\member-index.php on line 9"
我知道代码有问题，但我不知道如何解决。我的错误说：“注意：未定义变量：_SESSION in C:\xampp\htdocs\Smasher\member-index.php 第 9 行”
How can I fix the error so it will say the user's first name? The first name in the database table on mySQL is called fname.
如何修复错误以便它显示用户的名字？mySQL 上的数据库表中的第一个名称称为fname.
回答by Yassir Ennazk
Add
添加
session_start();
at the beginning of your page before any HTML
在任何 HTML 之前的页面开头
You will have something like :
你会有类似的东西：
<?php session_start();
include("inc/incfiles/header.inc.php")?>
<html>
<head>
<meta http-equiv="Content-Type" conte...
Don't forget to remove the space you have before
不要忘记删除您之前拥有的空间
回答by What have you tried
First, you'll need to add session_start()at the top of any page that you wish to use SESSIONvariables on.
首先，您需要在要session_start()在其上使用SESSION变量的任何页面的顶部添加。
Also, you should check to make sure the variable is set first before using it:
此外，您应该检查以确保在使用变量之前先设置变量：
if(isset($_SESSION['SESS_fname'])){
echo $_SESSION['SESS_fname'];
}
Or, simply:
或者，简单地说：
echo (isset($_SESSION['SESS_fname']) ? $_SESSION['SESS_fname'] : "Visitor");
