c#异步发送邮件的类

首先要定义一个邮件信息的基类，如下所示：

#region Properties
/// <summary>
/// Whom the message is to
/// </summary>
public virtual string To { get; set; }

/// <summary>
/// The subject of the email
/// </summary>
public virtual string Subject { get; set; }

/// <summary>
/// Whom the message is from
/// </summary>
public virtual string From { get; set; }

/// <summary>
/// Body of the text
/// </summary>
public virtual string Body { get; set; }

#endregion
}
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然后定义一个邮件的发送类，使用Netmail的方式发送邮件，发送邮件时采用了.net中自带的线程池，
通过多线程来实现异步的发送，代码如下：

/// <summary>
/// Default Constructor
/// </summary>
public EmailSender()
{
Attachments = new List<Attachment>();
EmbeddedResources = new List<LinkedResource>();
Priority = MailPriority.Normal;
}

#endregion

#region Public Functions

/// <summary>
/// Sends an email
/// </summary>
/// <param name="Message">The body of the message</param>
public void SendMail(string Message)
{
Body = Message;
SendMail();
}

/// <summary>
/// Sends a piece of mail asynchronous
/// </summary>
/// <param name="Message">Message to be sent</param>
public void SendMailAsync(string Message)
{
Body = Message;
ThreadPool.QueueUserWorkItem(delegate { SendMail(); });
}

/// <summary>
/// Sends an email
/// </summary>
public void SendMail()
{
using (System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage())
{
char[] Splitter = { ',', ';' };
string[] AddressCollection = To.Split(Splitter);
for (int x = 0; x < AddressCollection.Length; ++x)
{
if(!string.IsNullOrEmpty(AddressCollection[x].Trim()))
message.To.Add(AddressCollection[x]);
}
if (!string.IsNullOrEmpty(CC))
{
AddressCollection = CC.Split(Splitter);
for (int x = 0; x < AddressCollection.Length; ++x)
{
if (!string.IsNullOrEmpty(AddressCollection[x].Trim()))
message.CC.Add(AddressCollection[x]);
}
}
if (!string.IsNullOrEmpty(Bcc))
{
AddressCollection = Bcc.Split(Splitter);
for (int x = 0; x < AddressCollection.Length; ++x)
{
if (!string.IsNullOrEmpty(AddressCollection[x].Trim()))
message.Bcc.Add(AddressCollection[x]);
}
}
message.Subject = Subject;
message.From = new System.Net.Mail.MailAddress((From));
AlternateView BodyView = AlternateView.CreateAlternateViewFromString(Body, null, MediaTypeNames.Text.Html);
foreach (LinkedResource Resource in EmbeddedResources)
{
BodyView.LinkedResources.Add(Resource);
}
message.AlternateViews.Add(BodyView);
//message.Body = Body;
message.Priority = Priority;
message.SubjectEncoding = System.Text.Encoding.GetEncoding("ISO-8859-1");
message.BodyEncoding = System.Text.Encoding.GetEncoding("ISO-8859-1");
message.IsBodyHtml = true;
foreach (Attachment TempAttachment in Attachments)
{
message.Attachments.Add(TempAttachment);
}
System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient(Server, Port);
if (!string.IsNullOrEmpty(UserName) && !string.IsNullOrEmpty(Password))
{
smtp.Credentials = new System.Net.NetworkCredential(UserName, Password);
}
if (UseSSL)
smtp.EnableSsl = true;
else
smtp.EnableSsl = false;
smtp.Send(message);
}
}

/// <summary>
/// Sends a piece of mail asynchronous
/// </summary>
public void SendMailAsync()
{
ThreadPool.QueueUserWorkItem(delegate { SendMail(); });
}

#endregion

#region Properties

/// <summary>
/// Any attachments that are included with this
/// message.
/// </summary>
public List<Attachment> Attachments { get; set; }

/// <summary>
/// Any attachment (usually images) that need to be embedded in the message
/// </summary>
public List<LinkedResource> EmbeddedResources { get; set; }

/// <summary>
/// The priority of this message
/// </summary>
public MailPriority Priority { get; set; }

/// <summary>
/// Server Location
/// </summary>
public string Server { get; set; }

/// <summary>
/// User Name for the server
/// </summary>
public string UserName { get; set; }

/// <summary>
/// Password for the server
/// </summary>
public string Password { get; set; }

/// <summary>
/// Port to send the information on
/// </summary>
public int Port { get; set; }

/// <summary>
/// Decides whether we are using STARTTLS (SSL) or not
/// </summary>
public bool UseSSL { get; set; }

/// <summary>
/// Carbon copy send (seperate email addresses with a comma)
/// </summary>
public string CC { get; set; }

/// <summary>
/// Blind carbon copy send (seperate email addresses with a comma)
/// </summary>
public string Bcc { get; set; }

#endregion
}
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