我如何以这种形式添加reCaptcha？

Question

我想以这种形式添加Google reCaptcha我尝试了所有的事情，但都是徒劳的..我需要做的是使表单成功提交..并使用Ajax表单提交使reCaptcha成为必填字段...

HTML： -

<form id="contact-form" class="uk-form">
                        <fieldset>
                            <label>Name <em>*</em></label>
                            <input type="text" name="name" class="textfield" id="name" value="" />
                            <label>E-mail <em>*</em></label>
                            <input type="email" name="email" class="textfield" id="email" value="" />
                            <label>Services <em>*</em></label>
                            <input type="text" name="subject" class="textfield" id="subject" value="" />
                            <label>Message <em>*</em></label>
                            <textarea name="message" id="message" class="textarea" cols="2" rows="6"></textarea>
                            <div class="clearfix">
                                <div class="g-recaptcha" data-sitekey="My_Site_Key"></div>
                            </div>
                            <label>&nbsp;</label>
                            <button type="submit" name="submit" class="uk-button uk-button-small idz-button-blue" id="buttonsend">Submit</button>
                            <span class="loading" style="display: none;">Please wait..</span>
                        </fieldset>
                    </form>

JS： -
  $（＆＃39;＃buttonsend＆＃39;）。点击（function（）{

    var name    = $('#name').val();
    var subject = $('#subject').val();
    var email   = $('#email').val();
    var message = $('#message').val();

    $('.loading').fadeIn('fast');

    if (name != "" && subject != "" && email != "" && message != "")
        {

            $.ajax(
                {
                    url: './contact-us.php',
                    type: 'POST',
                    data: "name=" + name + "&subject=" + subject + "&email=" + email + "&message=" + message,
                    success: function(result) 
                    {
                        $('.loading').fadeOut('fast');
                        if(result == "email_error") {
                            $('#email').css({"background":"#FFFCFC","border":"1px solid #ffadad"}).next('.require').text(' !');
                        } else {
                            $('#name, #subject, #email, #message').val("","Name","Subject","Email","Message");
                            $('<div class="uk-alert uk-alert-success uk-text-center uk-margin-medium-bottom" data-uk-alert><p>Your message has been sent successfully. Thank you!</p></div>').insertBefore('#contact-form');
                            $('.uk-alert').fadeOut(5000, function(){ $(this).remove(); });
                        }
                    }
                }
            );
            return false;

        } 
    else 
        {
            $('.loading').fadeOut('fast');
            if( name == "","Name") $('#name').css({"background":"#FFFCFC","border":"1px solid #ffadad"});
            if(subject == "","Subject") $('#subject').css({"background":"#FFFCFC","border":"1px solid #ffadad"});
            if(email == "","Email" ) $('#email').css({"background":"#FFFCFC","border":"1px solid #ffadad"});
            if(message == "","Message") $('#message').css({"background":"#FFFCFC","border":"1px solid #ffadad"});
            return false;
        }
});

    $('#name, #subject, #email,#message').focus(function(){
        $(this).css({"border":"none","background":"#fafafa","border":"1px solid #ccc"});
    });

PHP： -

$to = "xyz@mydomain.com"; 
 $subject = "Contact Inquiry";
 $name = $_POST['name'];
 $email = $_POST['email'];
 $services = $_POST['subject'];
 $message = $_POST['message'];
 $str = "Name: ".$name."\r\n\r\n"."Services: ".$services."\r\n\r\n"."Message: ".$message."\r\n\r\n".
 $headers = "From: $email"; 
 $sent = mail($to, $subject, $str, $headers) ;