像按钮重定向到登录页面php

Question

我正致力于设计一个基本的社交媒体网站，我喜欢的按钮总是将我重定向到登录页面而不是实际上喜欢＆＃39;这篇文章。下面是我正在使用的代码。任何帮助都会很棒。

＆＃13;

＆＃13;

<?php
include('./classes/Login.php');

$isfollowing = False;
session_start();

if (!isset($_SESSION['username'])) {
	header('Location: login.php');
} else {
	$users = $_SESSION['username'];
}
	
$username = $_GET['u'];

if(DB::query("SELECT username, fname FROM users WHERE username='$username'")) {
	$user = $username;
		
	$userid = DB::query('SELECT id FROM users WHERE username=:username', array(':username'=>$username))[0]['id'];
	$followerid = $users;
		
	if(isset($_POST['post'])) {
		$userid = DB::query('SELECT id FROM users WHERE username=:username', array(':username'=>$username))[0]['id'];
		$postbody = $_POST['postbody'];
		if (strlen($postbody) > 300 || strlen($postbody) < 3) {
			
			die('Invalid Length.');
			
		}

			DB::query('INSERT INTO posts VALUES (\'\', :postbody, NOW(), :userid, 0)', array(':postbody'=>$postbody, ':userid'=>$userid));		
	}
	
	if(isset($_POST['like'])) {
		
	DB::query('UPDATE posts SET	likes = likes+1 where user_id=:user');
DB::query('INSERT INTO post_likes VALUES (\'\', :postid, :userid)', array(':postid'=>$postId, ':userid'=>$followerid));	
	
	}
	
	
	if(isset($_POST['unlike'])) {
		
	DB::query('UPDATE posts SET	likes = likes+1 where user_id=:user');
DB::query('DELETE FROM post_likes WHERE post_id=:postid AND user_id=:userid', array(':postid'=>$postId, ':userid'=>$followerid));
	
	}
	$dbposts = DB::query('SELECT * FROM posts WHERE user_id=:userid ORDER BY id DESC', array(':userid'=>$userid));
	$posts = "";
	foreach($dbposts as $p) {
		
		if(!DB::query('SELECT post_id FROM post_lilkes WHERE post_id=:postid AND user_id=:userid', array(':postid'=>$p['id'], ':userid'=>$users))) {
		$posts .= htmlspecialchars($p['body'])."
		<form action='profile.php?u=".$username."&postid=".$p['id']." method='post'>
			<input type='submit' name='like' value='Like!'>
			<span>".$p['likes']."</span>
			</form>
	<hr /></br />";
		} else {
			$posts .= htmlspecialchars($p['body'])."
			<form action='profile.php?u=".$username."&postid=".$p['id']." method='post'>
			<input type='submit' name='unlike' value='Unlike'>
			<span>" .$p['likes']."</span>
			</form>
	<hr /></br />";
		}
	}	
	
} else {
	header('Location: login.php');
}
?>

＆＃13;

＆＃13;

＆＃13;

运行var_dump($_SESSION, $_POST); exit;后，我得到以下输出：array(1) { ["username"]=> string(7) "ankoryx" } array(0) { }