aspx

Question

我想显示像旋转圆圈一样的预加载图像，请在按钮单击时等待文本等，并在功能完成时显示警告消息。 在我的方案按钮单击中，调用后面的代码方法来发送电子邮件。发送电子邮件时，我想显示预加载器，完成时应显示警告信息。以下是我的代码。

protected void btnSubmit1_Click(object sender, EventArgs e)
{
    const string esender = "emailid@email.com";
    const string sp = "password";
    string bodyMessage = "";
    //string text = txtmsg.text;
    try
    {
        SmtpClient smtp = new SmtpClient
        {
            Host = "smtp.gmail.com",
            Port = 587,
            EnableSsl = true,
            DeliveryMethod = SmtpDeliveryMethod.Network,
            Credentials = new System.Net.NetworkCredential(esender, sp),
            Timeout = 30000
        };
        bodyMessage = "Details of the sender\n" +
            "Name : " + txtName.Text + "\n\n" +
            "Email : " + txtemail.Text + "\n\n" +
            "Contact : " + txtNumber.Text + "\n\n" +
            "Subject : " + txtsubject.Text + "\n\n" +
            "Message : " + txtmsg.Text;
        MailMessage message = new MailMessage(esender, "receiver@gmail.com","Customer Enquiry", bodyMessage);
        smtp.Send(message);
    }
    catch (Exception ex)
    {

    }
}

按钮的

和aspx代码

<asp:Button ID="btnSubmit1" Text="Submit Message" class="btn btn-primary btn-lg"  OnClick="btnSubmit1_Click" runat="server" />