在成功调用ajax之后，通过php发送到ajax的数据未定义

Question

我在显示表单的响应警报时遇到了一些问题。

$(function () {

    // when the form is submitted
    $('#contact-form').on('submit', function (e) {

        // if the validator does not prevent form submit
        if (!e.isDefaultPrevented()) {
            var url = "contact.php";

            // POST values in the background the the script URL
            $.ajax({
                type: "POST",
                url: url,
                data: $(this).serialize(),
                success: function (data)
                {
                    // we recieve the type of the message: success x danger and apply it to the 
                    var messageAlert = 'alert-' + data.type;
                    var messageText = data.message;
                    // let's compose Bootstrap alert box HTML
                    var alertBox = '<div class="alert ' + messageAlert + ' alert-dismissable"><button type="button" class="close" data-dismiss="alert" aria-hidden="true">&times;</button>' + messageText + '</div>';
                    // If we have messageAlert and messageText
                    if (messageAlert && messageText) {
                        // inject the alert to .messages div in our form
                        $('#contact-form').find('.messages').html(alertBox);
                        // empty the form
                        $('#contact-form')[0].reset();
                    // }
                }
            });
            return false;
        }
    })
});

php文件看起来像这样

try
{

    if(count($_POST) == 0) throw new \Exception('Form is empty');

    $emailText = "You have a new message from your contact form\n=============================\n";

    foreach ($_POST as $key => $value) {
        // If the field exists in the $fields array, include it in the email 
        if (isset($fields[$key])) {
            $emailText .= "$fields[$key]: $value\n";
        }
    }

    // All the neccessary headers for the email.
    $headers = array('Content-Type: text/plain; charset="UTF-8";',
        'From: ' . $from,
        'Reply-To: ' . $from,
        'Return-Path: ' . $from,
    );

    // Send email
    mail($sendTo, $subject, $emailText, implode("\n", $headers));
    $responseArray = array('type' => 'success', 'message' => $okMessage);
}
catch (\Exception $e)
{
    $responseArray = array('type' => 'danger', 'message' => $errorMessage);
}

事实是，如果（messageAlert && messageText）永远都不为TRUE，因为那时变量未定义。 尽管电子邮件发送成功，并且js文件中的console.log（data）会打印所需的数据。

您能帮我解决问题吗？

Answer 1

您发送电子邮件，创建响应数组，但没有将其传递给ajax调用。 responseArray的回显在哪里？ 我建议您最好的方法是将其作为json数据传递：

echo json_encode($responseArray);

然后阅读javascript函数

var json = $.parseJSON(data);