如何在codeigniter php中单击提交按钮后显示成功弹出消息

Question

单击提交按钮后显示自定义弹出消息谢谢。我使用了codeigniter框架。我有一个部分作为请求表单，一旦用户填写数据并单击提交按钮，就会显示一条弹出消息谢谢你留言。这是我的代码。

<div class="col-md-3 requestfree">
    <img src="<?= base_url(); ?>theme/images/icon1.png" class="requesting">
    <h3 class="request">REQUEST</h3>
    <h5 class="free"> FREE QUOTE</h5>
    <h5 class="receive">You will receive quote within 24 hours</h5>
    <form name="contact"  id="contactform" enctype="multipart/form-data" method="post" action="<?php echo base_url();?>welcome/request">
        <?php if (isset($msg)): ?>
            <?= $msg; ?>
        <?php endif; ?>
        <div class="name"><span class="mandatory"></span>
            <input type="text" class="form-control" name="name" placeholder="Name" required>
            <?= form_error('name', '<div class="error">', '</div>'); ?>
        </div>
        <div class="name">
            <input type="text" class="form-control" name="phone" placeholder="Phone" required>
            <?= form_error('phone', '<div class="error">', '</div>'); ?>
        </div>
        <div class="email">
            <input type="email" class="form-control" name="email" placeholder="Email" required>
            <?= form_error('email', '<div class="error">', '</div>'); ?>
        </div>
        <div class="description">
            <textarea name="description"  style="width:100%;overflow:auto;" placeholder="Description" required></textarea>
        </div>
        <div class="">
            <div class="captchas">
                <img src="captcha.php?rand=<?= rand(); ?>" class="captchass" id='captchaimg'/>
                <p class="change"><a href="javascript: refreshCaptcha();" class="clickto">click to change</a></p>
            </div>
            <div class="captcha">
                <input type="text" class="form-control"id="captcha_code" name="captcha_code"  style="background-color: #EAD5D2;border: none;">
            </div>
        </div>
        <button type="submit" class="btn btn-success" onclick="return validate();">Submit</button>
        <p class="privacy">We respect your privacy</p>
    </form>
</div>

控制器：

function request()
{
    $this->load->library('form_validation');
        $this->form_validation->set_error_delimiters('<br /><span class="error"> ','</span>');
        $this->form_validation->set_rules('name','First Name' , 'required');
        $this->form_validation->set_rules('email','Email','required|valid_email');
        $this->form_validation->set_rules('phone','Mobile Number','required|numeric');
        $this->form_validation->set_rules('description','Description','required');
        if($this->form_validation->run()== FALSE)   
        {   
        $data['mainpage']='index';
        $this->load->view('templates/template',$data);
        }

    else
    {
        echo "hi";
        //get the form data
        $name = $this->input->post('name');
        $from_email = $this->input->post('email');
        $phone = $this->input->post('phone');
        $description = $this->input->post('description');       

        //set to_email id to which you want to receive mails
        $to_email = 'gmail@gmail.com';

        $config=Array(
    'protocol'=> 'smtp',
    'smtp_host' => 'ssl://smtp.gmail.com', //smtp host name
    'smtp_port' => '465', //smtp port number
    'smtp_user' => 'mail@gmail.com',
    'smtp_pass' => '*******', //$from_email password
    'mailtype' =>'html',
    'newline'  =>"\r\n",
    'crlf' =>"\r\n",
    'charset' => 'iso-8859-1',
    'wordwrap' => TRUE
    );

    $message            = array();


$message[] = 'Username  :  '.trim($name).' ';
$message[] = 'Phone Number :  '.trim($phone).' ';
$message[] = 'Description :  '.trim($description).' ';
$message = implode(PHP_EOL, $message);
    //send mail
    $this->load->library('email',$config);
    $this->email->from($from_email);
    $this->email->to($to_email);
    $this->email->subject('Request Free Quote');
    $this->email->message($message);
    $this->email->set_newline("\r\n");

        if ($this->email->send())
        {
            // mail sent
            $this->session->set_flashdata('msg','<div class="alert alert-success text-center">Your mail has been sent successfully!</div>');
            redirect('welcome');
        }
        else
        {
            //error
            $this->session->set_flashdata('msg','<div class="alert alert-danger text-center">There is error in sending mail! Please try again later</div>');
            redirect('welcome');
        }
    }
}