c#利用system.net发送html格式邮件

using system;
using system.text;
using system.net;
using system.net.mail;
using system.net.mime;

namespace leestudio.basic
{
/// <summary>
/// 邮件发送类
/// </summary>
public class sendemail
{
private mailmessage mailmessage = new mailmessage(); //实例化一个邮件类

#region 构造函数
/// <summary>
/// 构造函数
/// </summary>
/// <param name="toaddresses">收件人地址（多个以,号分开）</param>
/// <param name="fromaddress">发件人地址</param>
/// <param name="title">主题</param>
/// <param name="body">正文</param>
public sendemail(string toaddresses, string fromaddress, string title, string body)
: this(toaddresses, fromaddress, "", "", title, body, false)
{
}

/// <summary>
/// 构造函数
/// </summary>
/// <param name="toaddress">收件人地址</param>
/// <param name="fromaddress">发件人地址</param>
/// <param name="toname">收件人名字</param>
/// <param name="fromname">发件人姓名</param>
/// <param name="title">主题</param>
/// <param name="body">正文</param>
/// <param name="isbodyhtml">正文是否为html格式</param>
public sendemail(string toaddress, string fromaddress, string toname, string fromname, string title, string body, bool isbodyhtml)
{
mailmessage.from = new mailaddress(fromaddress, fromname, encoding.getencoding(936));
if (toname.equals(""))
mailmessage.to.add(toaddress);
else
mailmessage.to.add(new mailaddress(toaddress, toname, encoding.getencoding(936)));

mailmessage.subject = title;
mailmessage.subjectencoding = encoding.getencoding(936);

mailmessage.body = body;
mailmessage.isbodyhtml = isbodyhtml;
mailmessage.bodyencoding = encoding.getencoding(936);
}
#endregion

/// <summary>
/// 设置smtp，并且将邮件发送出去
/// 所有参数都设置完成后再调用该方法
/// </summary>
/// <param name="password">发件人密码</param>
/// <param name="smtphost">smtp服务器地址</param>
public void setsmtp(string password, string smtphost)
{
setsmtp(mailmessage.from.address, password, smtphost, 25, false, mailpriority.normal);
}

/// <summary>
/// 设置smtp，并且将邮件发送出去
/// 所有参数都设置完成后再调用该方法
/// </summary>
/// <param name="address">发件人地址（必须为真实有效的email地址）</param>
/// <param name="password">发件人密码</param>
/// <param name="smtphost">smtp服务器地址</param>
/// <param name="smtpport">smtp服务器的端口</param>
/// <param name="isenablessl">smtp服务器是否启用ssl加密</param>
/// <param name="priority">邮件的优先级</param>
public void setsmtp(string address, string password, string smtphost, int smtpport, bool isenablessl, mailpriority priority)
{
smtpclient smtp = new smtpclient();
smtp.deliverymethod = smtpdeliverymethod.network;
smtp.credentials = new networkcredential(address, password);
smtp.host = smtphost;
smtp.port = smtpport;
smtp.enablessl = isenablessl;

mailmessage.priority = priority;
smtp.send(mailmessage); //发送邮件
}

#region //设置邮件地址
/// <summary>
/// 设置更多收件人
/// </summary>
/// <param name="toaddresses">收件人地址</param>
public void setmoretoaddress(string toaddresses)
{
mailmessage.to.add(toaddresses);
}

/// <summary>
/// 设置更多收件人
/// </summary>
/// <param name="toaddresses">收件人地址</param>
/// <param name="toname">收件人名字</param>
public void setmoretoaddress(string toaddress, string toname)
{
mailmessage.to.add(new mailaddress(toaddress, toname, encoding.getencoding(936)));
}

/// <summary>
/// 设置抄送者（多个以,号分开）
/// </summary>
/// <param name="ccaddresses">抄送者地址</param>
public void setcarboncopyfor(string ccaddresses)
{
mailmessage.cc.add(ccaddresses);
}

/// <summary>
/// 设置抄送者
/// </summary>
/// <param name="ccaddress">抄送者地址</param>
/// <param name="ccname">抄送者名字</param>
public void setcarboncopyfor(string ccaddress, string ccname)
{
mailmessage.bcc.add(new mailaddress(ccaddress, ccname, encoding.getencoding(936)));
}

/// <summary>
/// 设置密送者（多个以,号分开）
/// </summary>
/// <param name="bccaddresses">密送者</param>
public void setblindcarboncopyfor(string bccaddresses)
{
mailmessage.bcc.add(bccaddresses);
}

/// <summary>
/// 设置密送者
/// </summary>
/// <param name="bccaddress">密送者</param>
/// <param name="bccname">密送者名字</param>
public void setblindcarboncopyfor(string bccaddress, string bccname)
{
mailmessage.bcc.add(new mailaddress(bccaddress, bccname, encoding.getencoding(936)));
}
#endregion

#region 添加附件
/// <summary>
/// 添加附件（自动识别文件类型）
/// </summary>
/// <param name="filename">单个文件的路径</param>
public void attachments(string filename)
{
mailmessage.attachments.add(new attachment(filename));
}

/// <summary>
/// 添加附件（默认为富文本rtf格式）
/// </summary>
/// <param name="filename">单个文件的路径</param>
public void attachmentsforrtf(string filename)
{
mailmessage.attachments.add(new attachment(filename, mediatypenames.application.rtf));
}
#endregion
}
}