1. How it Works

The system automatically looks for a file named admin_useredit_snippet.php in your active setup folder (e.g., setup_myapp/). If found, it is included in admin_useredit.php at two specific points:

2. Real-World Example: Sending Notification Emails

A common requirement is to send specific emails to users when their status changes (e.g., "Welcome to the Full Version" or "Account Archived"). Here is how we implemented this.

Step A: The UI (Adding Checkboxes)

We add switches to the form so the administrator can decide whether to send an email.

// --- PART 2: UI (Displayed in the form) ---
?>
<hr class="my-4">
<h4 class="h6 text-muted mb-3">Notifications & Actions</h4>

<div class="form-check form-switch mb-2">
    <input class="form-check-input" type="checkbox" role="switch" id="send_contract_mail" name="send_contract_mail" value="1">
    <label class="form-check-label" for="send_contract_mail">
        <i class="fa-solid fa-envelope me-2"></i>Send Welcome Mail (Contract)
    </label>
    <div class="form-text">Sends login data and shop link to the user.</div>
</div>

Step B: The Logic (Sending the Mail)

We check if the update was successful and if the checkbox was checked. Then we use PHPMailer to send a formatted HTML email.

<?php
// --- PART 1: LOGIC (Executed only after successful DB update) ---
if (isset($updated_rows) && $updated_rows > 0) {
    
    // 1. Check if the checkbox was selected
    if (!empty($_POST['send_contract_mail'])) {
        
        // 2. Prepare content
        $app_name = defined('SETUP_NAME') ? SETUP_NAME : 'My App';
        $subject = "Your License for " . $app_name;
        
        $body = "Hello <strong>" . htmlspecialchars($username) . "</strong>,\n\n";
        $body .= "Your account has been upgraded to 'Contract'.\n";
        // ... add more content ...

        // 3. Send Mail (using a helper function or PHPMailer directly)
        // Note: $email and $username are available from the main script scope
        $send_html_mail($email, $subject, nl2br($body), strip_tags($body));
    }

    // Important: Return to prevent the UI part from rendering during the redirect phase
    return; 
}
?>

3. More Ideas & Possibilities

The admin_useredit_snippet.php is a powerful tool. Here are some other things you can do with it: