javascript - 如何在单击提交按钮时将按钮替换为加载 gif 图像，然后成功删除表单并替换为成功消息

Question

我有一个 html 表单，并使用以下代码来处理它并验证输入字段。

sendmail.php:

if($_POST) {

    // Enter the email where you want to receive the message
    $emailTo = '<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="c1a4b9a0acb1ada481a6aca0a8adefa2aeac" rel="noreferrer noopener nofollow">[email protected]</a>';

    // Form fields
    $clientName = addslashes(trim($_POST['name']));
    $clientEmail = addslashes(trim($_POST['email']));
    $number = addslashes(trim($_POST['number']));
    $message = addslashes(trim($_POST['message']));

    // Email Ssubject
    $subject = 'Query from My Domain';

    // Compose message to send
    $sendMessage = 'Hi' . "\n\n";
    $sendMessage .= $message . "\n\n";
    $sendMessage .= 'From: ' . $clientName . "\n";
    $sendMessage .= 'Email: ' . $clientEmail . "\n";
    $sendMessage .= 'Contact number: ' . $number . "\n";

    $array = array();
    $array['nameMessage'] = '';
    $array['emailMessage'] = '';
    $array['numberMessage'] = '';
    $array['messageMessage'] = '';

    if($clientName == '') {
        $array['nameMessage'] = 'Please enter your full name.';
    }
    if (filter_var($clientEmail, FILTER_VALIDATE_EMAIL) == false) {
        $array['emailMessage'] = 'Please insert a valid email address.';
    } 
    if (!preg_match('/^(\+?)+([0-9]{10,})$/', $number)) {
        $array['numberMessage'] = 'Please enter a valid contact number.';
    }
    if($message == '') {
        $array['messageMessage'] = 'Please enter your message.';
    }

    $isValid = empty($array['nameMessage']) && empty($array['emailMessage']) &&
               empty($array['numberMessage']) && empty($array['messageMessage']);   

    if($isValid) {
        // build headers and send mail
        // Headers
        $headers = "From: " . $clientName . ' <' . $clientEmail . '>' . "\r\n";
        $headers .= "CC: " . 'My Boss <<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="8defe2fefecdeae0ece4e1a3eee2a3f7ec" rel="noreferrer noopener nofollow">[email protected]</a>>' . "\r\n";

        // Send mail
        mail($emailTo, $subject, $sendMessage, $headers);
    }   else {
            //echo the error messages
            echo json_encode($array); 
    }

}   else {
        header ('location: index.html#contact');
    }

?>

脚本.js:

$('.contact-form form').submit(function(e) {
    e.preventDefault();

    var form = $(this);
    var nameLabel = form.find('label[for="contact-name"]');
    var emailLabel = form.find('label[for="contact-email"]');
    var numberLabel = form.find('label[for="contact-number"]');
    var messageLabel = form.find('label[for="contact-message"]');

    nameLabel.html('Full name');
    emailLabel.html('Email');
    numberLabel.html('Contact number');
    messageLabel.html('Message');

    var postdata = form.serialize();

    $.ajax({
        type: 'POST',
        url: 'sendmail.php',
        data: postdata,
        dataType: 'json',
        success: function(json) {
            if(json.nameMessage !== '') {
                nameLabel.append(' - <span class="red error-label"> ' + json.nameMessage + '</span>');
            }
            if(json.emailMessage !== '') {
                emailLabel.append(' - <span class="red error-label"> ' + json.emailMessage + '</span>');
            }
            if(json.numberMessage !== '') {
                numberLabel.append(' - <span class="red error-label"> ' + json.numberMessage + '</span>');
            }
            if(json.messageMessage !== '') {
                messageLabel.append(' - <span class="red error-label"> ' + json.messageMessage + '</span>');
            }
        }
    });
});

表单工作得很好，我收到了电子邮件，我想做的就是向表单添加另外两个行为，当您单击提交按钮时，按钮内必须显示正在加载的 gif 图像，如果电子邮件发送成功，我想要删除表单并替换为成功消息。如果表单不是出于任何原因，我希望表单显示按钮以恢复到其初始状态。我该怎么做呢？

Answer 1

修改您的 script.js 代码，如下所示:

$('.contact-form form').submit(function(e) {
    e.preventDefault();
    $("#div-id").html('<img src="/images/loading.gif" />');

    var form = $(this);
    var nameLabel = form.find('label[for="contact-name"]');
    var emailLabel = form.find('label[for="contact-email"]');
    var numberLabel = form.find('label[for="contact-number"]');
    var messageLabel = form.find('label[for="contact-message"]');

    nameLabel.html('Full name');
    emailLabel.html('Email');
    numberLabel.html('Contact number');
    messageLabel.html('Message');

    var postdata = form.serialize();

    $.ajax({
        type: 'POST',
        url: 'sendmail.php',
        data: postdata,
        dataType: 'json',
        complete: function(){
          $("#div-id").html('<input type="submit" name="submit" value="submit">');
        },
        success: function(json) {
            if(json.nameMessage !== '') {
                nameLabel.append(' - <span class="red error-label"> ' + json.nameMessage + '</span>');
            }
            if(json.emailMessage !== '') {
                emailLabel.append(' - <span class="red error-label"> ' + json.emailMessage + '</span>');
            }
            if(json.numberMessage !== '') {
                numberLabel.append(' - <span class="red error-label"> ' + json.numberMessage + '</span>');
            }
            if(json.messageMessage !== '') {
                messageLabel.append(' - <span class="red error-label"> ' + json.messageMessage + '</span>');
            }
        }
    });
});

其中 div-id 是 HTML 模板中设置按钮的 div 元素的 id。

仅供您引用，有很多方法可以使用 jQuery 实现此目的。下面是一些引用文献。类似问题的链接

Change submit button to a loading image with jquery

Replace submit button with loading gif

http://www.willmaster.com/library/manage-forms/replacing-submit-button-with-loading-image.php