Example got on LinkedIn (https://www.linkedin.com/groups/3242849/3242849-6143986010788216834): https://github.com/glondon/signup/blob/master/gdform.php

send-email-gdform.php

// Example got on LinkedIn (https://www.linkedin.com/groups/3242849/3242849-6143986010788216834):
// https://github.com/glondon/signup/blob/master/gdform.php
<?php
  if (empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) !== 'xmlhttprequest')
    exit(header('Location: http://signupandmakemoney.com/info/ajax-error.html'));
  session_start();
  /* Don't need this anymore...
  $request_method = $_SERVER["REQUEST_METHOD"];
  if($request_method == "GET"){
    $query_vars = $_GET;
  } elseif ($request_method == "POST"){
    $query_vars = $_POST;
  }
  */
  if (!empty($_POST)) {
    $name = trim($_POST['first_name']);
    $email = trim($_POST['email']);
    $links = trim($_POST['links']);
    $questions = trim($_POST['questions']);
    $robot = trim($_POST['norobot']);
    $errors = array();
    if ($name == '')
      $errors['name'] = 'The name field is required';
    else if ($name == 'Name')
      $errors['name'] = 'The name field is required';
    else
      $errors['name'] = null;
    if ($email == '')
      $errors['email'] = 'The email field is required';
    else if ($email == 'Email')
      $errors['email'] = 'The email field is required';
    else if (filter_var($email, FILTER_VALIDATE_EMAIL) === false)
      $errors['email'] = $email . ' is not a valid email address';
    else
      $errors['email'] = null;
    //links & questions are not required...
    if ($links == '')
      $links = 'None'; 
    if ($links == 'Referral links for us to look at')
      $links = 'None';
    if ($questions == '')
      $questions = 'None';
    if ($questions == 'Questions/Comments')
      $questions = 'None';
    if ($robot == '')
      $errors['robot'] = 'The captcha field is required';
    else if ($robot == 'Enter Captcha')
      $errors['robot'] = 'The captcha field is required';
    else if (md5($robot) !== $_SESSION['randomnr2'])
      $errors['robot'] = 'The captcha field was incorrect';
    else
      $errors['robot'] = null;
    if ($errors['name'] !== null || $errors['email'] !== null || $errors['robot'] !== null) {
      $response['success'] = false;
      $response['nameError'] = $errors['name'];
      $response['emailError'] = $errors['email'];
      $response['robotError'] = $errors['robot'];
      header('Content-type: application/json; charset=utf-8');
      echo json_encode($response);
    } else {
      $response['success'] = true;
      $response['message'] = '<div class="success">We will be in contact with you shortly ' 
      . $name . '</div><script>$("#contact_us").hide(2000)</script>';
      //this header works in godaddy....
      $headers = 'Content-type: text/html; charset=iso-8859-1' . "\r\n";
      $headers .= 'From: Admin <info@signupandmakemoney.com>' . "\r\n";
      $toEmail = 'info@signupandmakemoney.com';
      $subject = 'You have a new contact form inquiry submission processed on ' . date('Y/m/d');
      $body = '<p>Inquiry details are below:</p>
        <ul>
          <li>Name: '.$name.'</li>
          <li>Email: '.$email.'</li>
          <li>Links: '.$links.'</li>
          <li>Questions: '.$questions.'</li>
        </ul>
        <p>Contact them ASAP!!!</p>';
      mail($toEmail, $subject, $body, $headers);
      header('Content-type: application/json; charset=utf-8');
      echo json_encode($response);
    }
  }
/* Don't need this anymore..
reset($query_vars);
$t = date("U");
$file = $_SERVER['DOCUMENT_ROOT'] . "/../data/gdform_" . $t;
$fp = fopen($file,"w");
while (list ($key, $val) = each ($query_vars)) {
 fputs($fp,"<GDFORM_VARIABLE NAME=$key START>\n");
 fputs($fp,"$val\n");
 fputs($fp,"<GDFORM_VARIABLE NAME=$key END>\n");
 if ($key == "redirect") { $landing_page = $val;}
}
fclose($fp);
if ($landing_page != "")
  header("Location: http://".$_SERVER["HTTP_HOST"]."/$landing_page");
else
  header("Location: http://".$_SERVER["HTTP_HOST"]."/");
*/
?>