How can PHP developers troubleshoot header redirection issues when using the header() function for login success?

When using the header() function for login success, PHP developers may encounter issues with header redirection not working as expected. This can be due to output being sent before the header function is called, causing headers already sent error. To solve this, developers can ensure that no output is sent before calling the header function by placing the header function at the very top of the PHP script.

<?php
ob_start(); // Start output buffering
// Your login authentication code here

if ($login_success) {
    header("Location: dashboard.php");
    exit();
} else {
    header("Location: login.php");
    exit();
}
ob_end_flush(); // Flush the output buffer
?>