我的PHP不会记录我的$\u会话

Question

所以我正在为PHP建立一个网站

<?php  
if(!empty($_SESSION['LoggedIn']) && !empty($_SESSION['Username'])) {   
    echo "<h1>Member Area</h1>"; 
    echo "<p>Thanks for logging in! You are <b>" . $_SESSION['Username'] . "</b> and your email address is <b>" . $_SESSION['EmailAddress'] . "</b>.</p>";    

} elseif(!empty($_POST['username']) && !empty($_POST['password'])) {  
    $username = mysql_real_escape_string($_POST['username']);  
    $password = md5(md5(mysql_real_escape_string($_POST['password'])));  

    $checklogin = mysql_query("SELECT * FROM users WHERE Username = '".$username."' AND Password = '".$password."'");  

    if(mysql_num_rows($checklogin) == 1) {  
        $row = mysql_fetch_array($checklogin);  
        $email = $row['EmailAddress'];  

        $_SESSION['Username'] = $username;  
        $_SESSION['EmailAddress'] = $email;  
        $_SESSION['LoggedIn'] = 1;  

        echo "<center>";
        echo "<h1>Success</h1>";  
        echo "<p>We are now redirecting you to the member area.</p>";  
        echo "<meta http-equiv='refresh' content='2;login.php' />";
        echo "</center>";  
    } else {  
        echo "<h1>Error</h1>";  
        echo "<p>Sorry, your account could not be found. Please <a href=\"login.php\">click here to try again</a>.</p>";  
    }  
} else {  
    echo "<center>";
    echo "<h1>Login</h1>";
    echo "<p>Thanks for visiting! Please either login below, or <a href=\"register.php\">click here to register</a>.</p>";
    echo "<form method=\"post\" action=\"login.php\" name=\"loginform\" id=\"loginform\">";
    echo "<label for=\"username\">Username:</label><input type=\"text\" name=\"username\" id=\"username\" /><br />";
    echo "<label for=\"password\">Password:</label><input type=\"password\" name=\"password\" id=\"password\" /><br /> "; 
    echo "<input type=\"submit\" name=\"login\" id=\"login\" value=\"Login\" />";
    echo "</form>";
    echo "</center>";
}  
?>

因此，基本上，页面加载并检查用户是否已登录，如果已登录，则加载成员区域。如果没有，它会检查用户是否正在尝试登录，如果没有，它会显示登录表单。我的问题是，每次我或其他人尝试登录时，页面都会重新加载，但不会将他们带到“成员”区域，而是将他们带回到登录表单。。。另外，在文档的顶部有一行：

编辑：注册用户的代码位于不同的php文件中。再一次，基地。带有session_start（）的php文件 包含在文档的顶部：if（！empty（$\u POST['username']）

    $checkusername = mysql_query("SELECT * FROM users WHERE Username = '".$username."'");  

    if(mysql_num_rows($checkusername) == 1) {  
        echo "<h1>Error</h1>";  
        echo "<p>Sorry, that username is taken. Please go back and try again.</p>";  
     } else {  
        $registerquery = mysql_query("INSERT INTO users (Username, Password, EmailAddress) VALUES('".$username."', '".$password."', '".$email."')");  
        if($registerquery) {  
            echo "<h1>Success</h1>";  
            echo "<p>Your account was successfully created. Please <a href=\"login.php\">click here to login</a>.</p>";  
        } else {  
            echo "<h1>Error</h1>";  
            echo "<p>Sorry, your registration failed. Please go back and try again.</p>";      
        }         
     }  
} else {  

   echo "<h1>Register</h1>";

   echo "<p>Please enter your details below to register.</p> "; 

    echo "<form method=\"post\" action=\"register.php\" name=\"registerform\" id=\"registerform\">";
    echo "    <label for=\"username\">Username:</label><input type=\"text\" name=\"username\" id=\"username\" /><br /> "; 
    echo "    <label for=\"password\">Password:</label><input type=\"password\" name=\"password\" id=\"password\" /><br />  ";
    echo "    <label for=\"email\">Email Address:</label><input type=\"text\" name=\"email\" id=\"email\" /><br />";  
    echo "    <input type=\"submit\" name=\"register\" id=\"register\" value=\"Register\" />"; 
    echo "</form>";   
}  
?>




Answer 1

对于你想把会话转移到的每一页，你必须这样做

session_start();

即使会话已经创建。

假设您想要一个注销页面，当您打算在类似注销的页面上注销用户时。php，您必须具备：

session_start();
session_destroy();

session_start（）；是破坏会话所必需的

Answer 2

始终确保session\u start（）也位于所有其他相关页面的顶部。我会使用isset来代替！空的。

session_start();
if(isset($_SESSION['LoggedIn']) && isset($_SESSION['Username'])) {

Answer 3

你好像错过了一个机会

session_start()

在php脚本的顶部