C#发送邮件

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Net.Mail;
using System.ComponentModel;

public partial class WebMail_Mail : System.Web.UI.Page
{
    static bool mailSent = false;
    static string ReturnString = "";
    public static void SendCompletedCallback(object sender, AsyncCompletedEventArgs e)
    {
        // Get the unique identifier for this asynchronous operation.
        String token = (string)e.UserState;

        if (e.Cancelled)
        {
            ReturnString = token + " Send canceled.";
            //Response.Write(ss);
        }
        if (e.Error != null)
        {
            //Response.Write(token +"  "+e.Error.ToString());
            ReturnString = token + "  " + e.Error.ToString();
        }
        else
        {
            //Response.Write("Message sent.");
            ReturnString = "Message sent.";
        }
        mailSent = true;
    }

    protected void Page_Load(object sender, EventArgs e)
    {
        /*
        MailMessage msg = new MailMessage();
        //
        MailAddress Fr_address = new MailAddress("oapro_test@163.com", "oapro_test");
        MailAddressCollection cc_address = new MailAddressCollection();
        cc_address.Add("oapro_test@163.com");

      

        msg.From = Fr_address;
       
        msg.Subject = "this is a test By bxf";
        msg.Body = "白肖凤测试";
        //身份严正
        System.Net.ICredentialsByHost Credential;
       

        //
        SmtpClient smtp = new SmtpClient("smtp.163.com",25);
        smtp.Timeout = 30;
        //smtp.Send(msg);
        smtp.Credentials =
         */
        /*
        System.Net.Mail.SmtpClient client = new SmtpClient("smtp.163.com",25);
        client.UseDefaultCredentials = true;
        client.Credentials = new System.Net.NetworkCredential("oapro_test", "");
        client.DeliveryMethod = SmtpDeliveryMethod.Network;

        System.Net.Mail.MailMessage message = new MailMessage("oapro_test@163.com", "oapro_test@163.com", "this is a test By bxf", "白肖凤测试");
        message.BodyEncoding = System.Text.Encoding.UTF8;
        message.IsBodyHtml = true;

        try
        {
            client.Send(message);
        }
        catch (System.Net.Mail.SmtpException ex)
        {
            Response.Write(ex.ToString());
        }
        )*/
         // Command line argument must the the SMTP host.
            SmtpClient client = new SmtpClient("smtp.163.com",25);
           
        //验证
            client.UseDefaultCredentials = true;
            client.Credentials = new System.Net.NetworkCredential("", "");
            client.DeliveryMethod = SmtpDeliveryMethod.Network;

            // Specify the e-mail sender.
            // Create a mailing address that includes a UTF8 character
            // in the display name.
            MailAddress from = new MailAddress("bxf0011@163.com",
               "Jane " + (char)0xD8+ " Clayton",
            System.Text.Encoding.UTF8);
            // Set destinations for the e-mail message.
            MailAddress to = new MailAddress("oapro_test@163.com");
            // Specify the message content.
            MailMessage message = new MailMessage(from, to);
            message.Body = "This is a test e-mail message sent by an application. ";
            // Include some non-ASCII characters in body and subject.
            string someArrows = new string(new char[] {'\u2190', '\u2191', '\u2192', '\u2193'});
            message.Body += Environment.NewLine + someArrows;
            message.BodyEncoding =  System.Text.Encoding.UTF8;
            message.Subject = "test message 1" + someArrows;
            message.SubjectEncoding = System.Text.Encoding.UTF8;

            // Set the method that is called back when the send operation ends.
            client.SendCompleted += new
            SendCompletedEventHandler(SendCompletedCallback);
            // The userState can be any object that allows your callback
            // method to identify this send operation.
            // For this example, the userToken is a string constant.
            string userState = "test message1";

             try
            {
               
               // client.SendAsync(message, userState);
               client.Send(message);
                Response.Write("Sending message... press c to cancel mail. Press any other key to exit.");

                string answer = ReturnString;
                // If the user canceled the send, and mail hasn't been sent yet,
                // then cancel the pending operation.
                if (answer.StartsWith("c") && mailSent == false)
                {
                    client.SendAsyncCancel();
                }
                // Clean up.
                message.Dispose();
                Response.Write("Goodbye.");
            }
            catch (System.Net.Mail.SmtpException ex)
            {
                Response.Write(ex.ToString());
            }

    }

}