在一个位置连接php变量

Depending on the variable found, I'd like that the user connect to a dedicated page.

Here is the part of my code :

session_start();
$_SESSION['username'] = $username;                          
header("location: welcome.php");

Instead of "welcome.php", I'd like to have "location: welcome_$username.php"

How can I achieve that ? I've tried with echo but it seems I don't understand enough php to find my mistakes.

<?php

$user='test';
header("location: welcome_"."$user".'.php');

And the redirection leads to

http://localhost/welcome_test.php

welcome_$username.php Will give you a 404 Error after redirecting, lets say the username of that user is John

Your file will be welcome_john.php which I'm positive it does not exist on your file system rather user a query string.

Then have

header("location: welcome.php?username=".$_SESSION['username']);

Then on welcome use the query string to show different users what ever they need to see on welcome