在不离开页面和bootstrapValidator的情况下发送联系表格

我正在使用codepen中的此代码作为我的联系人表单。

我遇到的问题是，一旦你点击"发送"按钮，你就会离开联系人表格到达的页面，进入sendmessage.php。

我希望看到的是表单的正常行为：当你点击"发送"（消息成功传输）时，你停留在同一页面上，"发送"按钮消失，取而代之的是"成功"消息，而不离开或重新加载表单所在的页面。。

知道当前代码的问题是什么吗？你可以在这里测试我的实例

非常感谢，

HTML:

<form class="well form-horizontal" action="../sendmessage.php" method="post"  id="contact_form">

Javascript：

  $(document).ready(function() {
    $('#contact_form').bootstrapValidator({
        // To use feedback icons, ensure that you use Bootstrap v3.1.0 or later
        feedbackIcons: {
            valid: 'glyphicon glyphicon-ok',
            invalid: 'glyphicon glyphicon-remove',
            validating: 'glyphicon glyphicon-refresh'
        },
        fields: {
            first_name: {
                validators: {
                        stringLength: {
                        min: 2,
                    },
                        notEmpty: {
                        message: 'Please supply your first name'
                    }
                }
            },
            email: {
                validators: {
                    notEmpty: {
                        message: 'Please supply your email address'
                    },
                    emailAddress: {
                        message: 'Please supply a valid email address'
                    }
                }
            },            
            message: {
                validators: {
                      stringLength: {
                        min: 10,
                        max: 200,
                        message:'Please enter at least 10 characters and no more than 200'
                    },
                    notEmpty: {
                        message: 'Please supply a description of your project'
                    }
                    }
                }
            }
        })
        .on('success.form.bv', function(e) {
            $('#success_message').slideDown({ opacity: "show" }, "slow") // Do something ...
                $('#contact_form').data('bootstrapValidator').resetForm();
            // Prevent form submission
            e.preventDefault();
            // Get the form instance
            var $form = $(e.target);
            // Get the BootstrapValidator instance
            var bv = $form.data('bootstrapValidator');
            // Use Ajax to submit form data
            $.post($form.attr('action'), $form.serialize(), function(result) {
                console.log(result);
            }, 'json');
        });
});

sendmessage.php的内容：

<?php
require 'PHPMailer/PHPMailerAutoload.php';
$mail = new PHPMailer;
$mail->CharSet = 'utf-8';
//Enable SMTP debugging. 
$mail->SMTPDebug = false;                               
//Set PHPMailer to use SMTP.
$mail->isSMTP();            
//Set SMTP host name                          
$mail->Host = "smtp.elasticemail.com";
//Set this to true if SMTP host requires authentication to send email
$mail->SMTPAuth = true;                          
//Provide username and password     
$mail->Username = "xyz";                 
$mail->Password = "xyz";                           
//If SMTP requires TLS encryption then set it
$mail->SMTPSecure = "tls";                           
//Set TCP port to connect to 
$mail->Port = 2525;                                   
$mail->From = $_POST['email'];
$mail->FromName = $_POST['first_name'];
$mail->addAddress("xyz@gmail.com");
//CC and BCC
$mail->addCC("xyz@outlook.com");
$mail->addBCC("");
$mail->isHTML(true);
$mail->Subject = "New message from " . $_POST['first_name'] . $_POST['last_name'];
$mail->Body =  $_POST['message']."<br><br>From page: ". str_replace("http://", "", $_SERVER['HTTP_REFERER']) . "<br>" . $_SERVER ['HTTP_USER_AGENT'] ;
$response = array();
if(!$mail->send()) {
  $response = array('message'=>"Mailer Error: " . $mail->ErrorInfo, 'status'=> 0);
} else {
  $response = array('message'=>"Message has been sent successfully", 'status'=> 1);
}
/* send content type header */
header('Content-Type: application/json');
/* send response as json */
echo json_encode($response);
?>