How can PHP developers differentiate between code-related login issues and server/browser-related login issues?

To differentiate between code-related login issues and server/browser-related login issues, PHP developers can start by checking if the login functionality works correctly when testing on different browsers or devices. If the issue persists across all platforms, it is likely a code-related problem. Developers can also inspect the server logs to see if any errors are being thrown during the login process, which could indicate a server-side issue.

// Sample code to check if the login functionality is working correctly

if($login_successful){
    // Redirect user to dashboard
    header("Location: dashboard.php");
    exit();
} else {
    // Display error message
    echo "Invalid username or password. Please try again.";
}