在使用电子邮件ID登录时，会话开始不显示用户名[复制]

Question

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• How to fix “Headers already sent” error in PHP 11 answers

I have been using the following code for beginning sessions, but I can't show the username after 'welcome'. How can I do that? I am using email and id for logging in. The email, id and username are stored in MySQL. Also when logged in, the login button should disappear, and the logout button should appear.

<div class="hello"> 

<?php  
  session_start();  
  require_once("config.php");  
  if (!(isset($_SESSION['login']) && $_SESSION['login'] != '')) 
  {  
    header ("Location: login.html");  
    exit;  
  }  
  else  
  {  
    echo "Welcome </b>,  <a href=logout.php>Logout</a> <br><br>";  
  }  
?>

</div> 

</div>

Answer 1

header() and session_start() must both come before any HTML. You can set $_SESSION['username'] and $_SESSION['email'] where you process the login info.