How can PHP be used to send an email notification after a certain number of form submissions, such as 1000?

To send an email notification after a certain number of form submissions, such as 1000, you can keep track of the number of submissions in a database or a file. When a form is submitted, increment the submission count and check if it has reached the desired number. If it has, use PHP's `mail()` function to send an email notification.

// Assuming you have a database connection established

// Increment submission count
$submissionCount = // Retrieve submission count from database
$submissionCount++;

// Update submission count in database
// UPDATE submission_count_table SET count = $submissionCount

// Check if submission count has reached 1000
if ($submissionCount == 1000) {
    $to = "recipient@example.com";
    $subject = "1000 form submissions reached";
    $message = "The form has been submitted 1000 times.";
    $headers = "From: sender@example.com";

    // Send email notification
    mail($to, $subject, $message, $headers);
}