<form action="includes/register.php" class="form__signup" id="register-form" method="POST">
          <a href="" class="reg-close"></a>
          <div class="form__header">
            <h2 class="form__title">Регистрация</h2>
          </div> <!-- ====== form__header ====== -->
          <div class="form__msg" class="msgs"></div>
          <div class="form__group">
            <input type="text" class="form__control" placeholder="Ваше имя" name="full_name" id="full_name" />
          </div>
          <div class="form__group">
            <input type="email" class="form__control" placeholder="Ваш Email" name="email" id="email">
          </div>
          <div class="form__group">
            <input type="text" class="form__control" placeholder="Ваш логин" name="username" id="username">
          </div>
          <div class="form__group">
            <input type="password" class="form__control" placeholder="Ваш пароль" name="password" id="password" />
          </div>
          <div class="form__group">
            <input type="password" class="form__control" placeholder="Подтвердите пароль" name="cpassword" id="cpassword" />
          </div>
          <div class="form__group">
            <button type="submit" class="form__btn" name="do-signup" id="btn-submit">Регистрация</button>
          </div>
        </form>

require_once 'connection.php';

if(isset($_POST["do-signup"])){


    if(!empty($_POST['full_name']) && !empty($_POST['email']) && !empty($_POST['username']) && !empty($_POST['password']) &&(!empty($_POST['cpassword'])) && $_POST['password'] == $_POST['cpassword'] ) {
        $full_name=$_POST['full_name'];
        $email=$_POST['email'];
        $username=$_POST['username'];
        $password=$_POST['password'];



        $query=mysql_query("SELECT * FROM users WHERE username='".$username."'");
        $numrows=mysql_num_rows($query);

        if($numrows==0)
        {
        $sql="INSERT INTO users
                (full_name, email, username,password)
                VALUES('$full_name','$email', '$username', '$password')";

        $result=mysql_query($sql);

        if($result){
            $messages = "Account Successfully Created";
           } else {
            $messages = "Failed to insert data information!";
           }

           } else {
            $messages = "That username already exists! Please try another one!";
           }

       } else {
            $messages = "All fields are required!";
       }

function submitForm()
    {
        var data = $("#register-form").serialize();
        var formNm=$("#refister-form");
        var message=$(formNm).find(".msgs");
        var formTitle=$(formNm).find(".formTitle");

        $.ajax({

            type : 'POST',
            url  : '../includes/register.php',
            data : data,
            beforeSend: function()
            {
                $("#btn-submit").html('<span></span> &nbsp; sending ...');
            },
            success :  function(data)
            {
                message.html('');
                formTitle.css("display","none");
                setTimeout(function(){
                  $('.formTitle').css("display","block");
                  $('.msgs').html(data);
                  $('input').not(':input[type=submit], :input[type=hidden]').val('');
                }
                ,3000);
            }
        });
        return false;
    }