有没有发邮件的类在winform中? System.Web.Mail命名空间:http://www.codeproject.com/csharp/sendmailcsharp.asp 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 论坛搜集的//============================================================// File: MailSender.cs// 邮件发送组件// 支持ESMTP, 多附件//============================================================namespace JcPersonal.Utility{ using System; using System.Collections; using System.Net.Sockets; using System.IO; using System.Text; /// <summary> /// Mail 发送器 /// </summary> public class MailSender { /// <summary> /// SMTP服务器域名 /// </summary> public string Server { get { return server; } set { if (value != server) server = value; } } private string server = ""; /// <summary> /// SMTP服务器端口 [默认为25] /// </summary> public int Port { get { return port; } set { if (value != port) port = value; } } private int port = 25; /// <summary> /// 用户名 [如果需要身份验证的话] /// </summary> public string UserName { get { return userName; } set { if (value != userName) userName = value; } } private string userName = ""; /// <summary> /// 密码 [如果需要身份验证的话] /// </summary> public string Password { get { return password; } set { if (value != password) password = value; } } private string password = ""; /// <summary> /// 发件人地址 /// </summary> public string From { get { return from; } set { if (value != from) from = value;} } private string from = ""; /// <summary> /// 收件人地址 /// </summary> public string To { get { return to; } set { if (value != to) to = value;} } private string to = ""; /// <summary> /// 发件人姓名 /// </summary> public string FromName { get { return fromName; } set { if (value != fromName) fromName = value; } } private string fromName = ""; /// <summary> /// 收件人姓名 /// </summary> public string ToName { get { return toName; } set { if (value != toName) toName = value; } } private string toName = ""; /// <summary> /// 邮件的主题 /// </summary> public string Subject { get { return subject; } set { if (value != subject) subject = value; } } private string subject = ""; /// <summary> /// 邮件正文 /// </summary> public string Body { get { return body; } set { if (value != body) body = value; } } private string body = ""; /// <summary> /// 超文本格式的邮件正文 /// </summary> public string HtmlBody { get { return htmlBody; } set { if (value != htmlBody) htmlBody = value; } } private string htmlBody = ""; /// <summary> /// 是否是html格式的邮件 /// </summary> public bool IsHtml { get { return isHtml; } set { if (value != isHtml) isHtml = value; } } private bool isHtml = false; /// <summary> /// 语言编码 [默认为GB2312] /// </summary> public string LanguageEncoding { get { return languageEncoding; } set { if (value != languageEncoding) languageEncoding = value; } } private string languageEncoding = "GB2312"; /// <summary> /// 邮件编码 [默认为8bit] /// </summary> public string MailEncoding { get { return encoding; } set { if (value != encoding) encoding = value; } } private string encoding = "8bit"; /// <summary> /// 邮件优先级 [默认为3] /// </summary> public int Priority { get { return priority; } set { if (value != priority) priority = value; } } private int priority = 3; /// <summary> /// 附件 [AttachmentInfo] /// </summary> public IList Attachments { get { return attachments; }// set { if (value != attachments) attachments = value; } } private ArrayList attachments = new ArrayList (); /// <summary> /// 发送邮件 /// </summary> public void SendMail () { // 创建TcpClient对象, 并建立连接 TcpClient tcp = null; try { tcp = new TcpClient (server, port); } catch (Exception) { throw new Exception ("无法连接服务器"); } ReadString (tcp.GetStream());//获取连接信息 // 开始进行服务器认证 // 如果状态码是250则表示操作成功 if (!Command (tcp.GetStream(), "EHLO Localhost", "250")) throw new Exception ("登陆阶段失败"); if (userName != "") { // 需要身份验证 if (!Command (tcp.GetStream(), "AUTH LOGIN", "334")) throw new Exception ("身份验证阶段失败"); string nameB64 = ToBase64 (userName); // 此处将username转换为Base64码 if (!Command (tcp.GetStream(), nameB64, "334")) throw new Exception ("身份验证阶段失败"); string passB64 = ToBase64 (password); // 此处将password转换为Base64码 if (!Command (tcp.GetStream(), passB64, "235")) throw new Exception ("身份验证阶段失败"); } // 准备发送 WriteString (tcp.GetStream(), "mail From: " + from); WriteString (tcp.GetStream(), "rcpt to: " + to); WriteString (tcp.GetStream(), "data"); // 发送邮件头 WriteString (tcp.GetStream(), "Date: " + DateTime.Now); // 时间 WriteString (tcp.GetStream(), "From: " + fromName + "<" + from + ">"); // 发件人 WriteString (tcp.GetStream(), "Subject: " + subject); // 主题 WriteString (tcp.GetStream(), "To:" + toName + "<" + to + ">"); // 收件人 //邮件格式 WriteString (tcp.GetStream(), "Content-Type: multipart/mixed; boundary=\"unique-boundary-1\""); WriteString (tcp.GetStream(), "Reply-To:" + from); // 回复地址 WriteString (tcp.GetStream(), "X-Priority:" + priority); // 优先级 WriteString (tcp.GetStream(), "MIME-Version:1.0"); // MIME版本 // 数据ID,随意// WriteString (tcp.GetStream(), "Message-Id: " + DateTime.Now.ToFileTime() + "@security.com"); WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding); // 内容编码 WriteString (tcp.GetStream(), "X-Mailer:JcPersonal.Utility.MailSender"); // 邮件发送者 WriteString (tcp.GetStream(), ""); WriteString (tcp.GetStream(), ToBase64 ("This is a multi-part message in MIME format.")); WriteString (tcp.GetStream(), ""); // 从此处开始进行分隔输入 WriteString (tcp.GetStream(), "--unique-boundary-1"); // 在此处定义第二个分隔符 WriteString (tcp.GetStream(), "Content-Type: multipart/alternative;Boundary=\"unique-boundary-2\""); WriteString (tcp.GetStream(), ""); if(!isHtml) { // 文本信息 WriteString (tcp.GetStream(), "--unique-boundary-2"); WriteString (tcp.GetStream(), "Content-Type: text/plain;charset=" + languageEncoding); WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding); WriteString (tcp.GetStream(), ""); WriteString (tcp.GetStream(), body); WriteString (tcp.GetStream(), "");//一个部分写完之后就写如空信息,分段 WriteString (tcp.GetStream(), "--unique-boundary-2--");//分隔符的结束符号,尾巴后面多了-- WriteString (tcp.GetStream(), ""); } else { //html信息 WriteString (tcp.GetStream(), "--unique-boundary-2"); WriteString (tcp.GetStream(), "Content-Type: text/html;charset=" + languageEncoding); WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding); WriteString (tcp.GetStream(), ""); WriteString (tcp.GetStream(), htmlBody); WriteString (tcp.GetStream(), ""); WriteString (tcp.GetStream(), "--unique-boundary-2--");//分隔符的结束符号,尾巴后面多了-- WriteString (tcp.GetStream(), ""); } // 发送附件,承上 // 对文件列表做循环 for (int i = 0; i < attachments.Count; i++) { WriteString (tcp.GetStream(), "--unique-boundary-1"); // 邮件内容分隔符 WriteString (tcp.GetStream(), "Content-Type: application/octet-stream;name=\"" + ((AttachmentInfo)attachments[i]).FileName + "\""); // 文件格式 WriteString (tcp.GetStream(), "Content-Transfer-Encoding: base64"); // 内容的编码 WriteString (tcp.GetStream(), "Content-Disposition:attachment;filename=\"" + ((AttachmentInfo)attachments[i]).FileName + "\""); // 文件名 WriteString (tcp.GetStream(), ""); WriteString (tcp.GetStream(), ((AttachmentInfo)attachments[i]).Bytes); // 写入文件的内容 WriteString (tcp.GetStream(), ""); } Command (tcp.GetStream(), ".", "250"); // 最后写完了,输入"." // 关闭连接 tcp.Close (); } /// <summary> /// 向流中写入字符 /// </summary> /// <param name="netStream">来自TcpClient的流</param> /// <param name="str">写入的字符</param> protected void WriteString (NetworkStream netStream, string str) { str = str + "\r\n"; // 加入换行符 // 将命令行转化为byte[] byte[] bWrite = Encoding.GetEncoding(languageEncoding).GetBytes(str.ToCharArray()); // 由于每次写入的数据大小是有限制的,那么我们将每次写入的数据长度定在75个字节,一旦命令长度超过了75,就分步写入。 int start=0; int length=bWrite.Length; int page=0; int size=75; int count=size; try { if (length>75) { // 数据分页 if ((length/size)*size<length) page=length/size+1; else page=length/size; for (int i=0;i<page;i++) { start=i*size; if (i==page-1) count=length-(i*size); netStream.Write(bWrite,start,count);// 将数据写入到服务器上 } } else netStream.Write(bWrite,0,bWrite.Length); } catch(Exception) { // 忽略错误 } } /// <summary> /// 从流中读取字符 /// </summary> /// <param name="netStream">来自TcpClient的流</param> /// <returns>读取的字符</returns> protected string ReadString (NetworkStream netStream) { string sp = null; byte[] by = new byte[1024]; int size = netStream.Read(by,0,by.Length);// 读取数据流 if (size > 0) { sp = Encoding.Default.GetString(by);// 转化为String } return sp; } /// <summary> /// 发出命令并判断返回信息是否正确 /// </summary> /// <param name="netStream">来自TcpClient的流</param> /// <param name="command">命令</param> /// <param name="state">正确的状态码</param> /// <returns>是否正确</returns> protected bool Command (NetworkStream netStream, string command, string state) { string sp=null; bool success=false; try { WriteString (netStream, command);// 写入命令 sp = ReadString (netStream);// 接受返回信息 if (sp.IndexOf(state) != -1)// 判断状态码是否正确 success=true; } catch(Exception) { // 忽略错误 } return success; } /// <summary> /// 字符串编码为Base64 /// </summary> /// <param name="str">字符串</param> /// <returns>Base64编码的字符串</returns> protected string ToBase64 (string str) { try { byte[] by = Encoding.Default.GetBytes (str.ToCharArray()); str = Convert.ToBase64String (by); } catch(Exception) { // 忽略错误 } return str; } /// <summary> /// 附件信息 /// </summary> public struct AttachmentInfo { /// <summary> /// 附件的文件名 [如果输入路径,则自动转换为文件名] /// </summary> public string FileName { get { return fileName; } set { fileName = Path.GetFileName(value); } } private string fileName; /// <summary> /// 附件的内容 [由经Base64编码的字节组成] /// </summary> public string Bytes { get { return bytes; } set { if (value != bytes) bytes = value; } } private string bytes; /// <summary> /// 从流中读取附件内容并构造 /// </summary> /// <param name="ifileName">附件的文件名</param> /// <param name="stream">流</param> public AttachmentInfo (string ifileName, Stream stream) { fileName = Path.GetFileName (ifileName); byte[] by = new byte [stream.Length]; stream.Read (by,0,(int)stream.Length); // 读取文件内容 //格式转换 bytes = Convert.ToBase64String (by); // 转化为base64编码 } /// <summary> /// 按照给定的字节构造附件 /// </summary> /// <param name="ifileName">附件的文件名</param> /// <param name="ibytes">附件的内容 [字节]</param> public AttachmentInfo (string ifileName, byte[] ibytes) { fileName = Path.GetFileName (ifileName); bytes = Convert.ToBase64String (ibytes); // 转化为base64编码 } /// <summary> /// 从文件载入并构造 /// </summary> /// <param name="path"></param> public AttachmentInfo (string path) { fileName = Path.GetFileName (path); FileStream file = new FileStream (path, FileMode.Open); byte[] by = new byte [file.Length]; file.Read (by,0,(int)file.Length); // 读取文件内容 //格式转换 bytes = Convert.ToBase64String (by); // 转化为base64编码 file.Close (); } } }} [求助]C#开发WAP页面的时候,内容怎么分页显示? 获取文件路径 用C#连ORACLE进行增查等操作的时候老提示无效字符串!!怎么办?? WinForm中如何设置DataGridView列的位置 C# 帮忙翻译一段JAVA的MD5代码 转成C# 谢谢 定义一个类,包含各种类型,如何获得占用了多少字节 高手请进,c#的SetWindowsHookEx总是返回0,钩子不能钩住另外一个process的程序! 是不是这样的呢? 电子手写签名,电子图章 duwawish7.0安装问题,在线等待......... DataGrid怎样保持对DataSet同步的显示(请高手......)
论坛搜集的
//============================================================
// File: MailSender.cs
// 邮件发送组件
// 支持ESMTP, 多附件
//============================================================namespace JcPersonal.Utility
{
using System;
using System.Collections;
using System.Net.Sockets;
using System.IO;
using System.Text; /// <summary>
/// Mail 发送器
/// </summary>
public class MailSender
{
/// <summary>
/// SMTP服务器域名
/// </summary>
public string Server {
get { return server; }
set { if (value != server) server = value; }
} private string server = ""; /// <summary>
/// SMTP服务器端口 [默认为25]
/// </summary>
public int Port {
get { return port; }
set { if (value != port) port = value; }
} private int port = 25; /// <summary>
/// 用户名 [如果需要身份验证的话]
/// </summary>
public string UserName {
get { return userName; }
set { if (value != userName) userName = value; }
} private string userName = ""; /// <summary>
/// 密码 [如果需要身份验证的话]
/// </summary>
public string Password {
get { return password; }
set { if (value != password) password = value; }
} private string password = ""; /// <summary>
/// 发件人地址
/// </summary>
public string From {
get { return from; }
set { if (value != from) from = value;}
} private string from = ""; /// <summary>
/// 收件人地址
/// </summary>
public string To {
get { return to; }
set { if (value != to) to = value;}
} private string to = ""; /// <summary>
/// 发件人姓名
/// </summary>
public string FromName {
get { return fromName; }
set { if (value != fromName) fromName = value; }
} private string fromName = ""; /// <summary>
/// 收件人姓名
/// </summary>
public string ToName {
get { return toName; }
set { if (value != toName) toName = value; }
} private string toName = ""; /// <summary>
/// 邮件的主题
/// </summary>
public string Subject {
get { return subject; }
set { if (value != subject) subject = value; }
} private string subject = ""; /// <summary>
/// 邮件正文
/// </summary>
public string Body {
get { return body; }
set { if (value != body) body = value; }
} private string body = ""; /// <summary>
/// 超文本格式的邮件正文
/// </summary>
public string HtmlBody {
get { return htmlBody; }
set { if (value != htmlBody) htmlBody = value; }
} private string htmlBody = ""; /// <summary>
/// 是否是html格式的邮件
/// </summary>
public bool IsHtml {
get { return isHtml; }
set { if (value != isHtml) isHtml = value; }
} private bool isHtml = false; /// <summary>
/// 语言编码 [默认为GB2312]
/// </summary>
public string LanguageEncoding {
get { return languageEncoding; }
set { if (value != languageEncoding) languageEncoding = value; }
} private string languageEncoding = "GB2312"; /// <summary>
/// 邮件编码 [默认为8bit]
/// </summary>
public string MailEncoding {
get { return encoding; }
set { if (value != encoding) encoding = value; }
} private string encoding = "8bit"; /// <summary>
/// 邮件优先级 [默认为3]
/// </summary>
public int Priority {
get { return priority; }
set { if (value != priority) priority = value; }
} private int priority = 3; /// <summary>
/// 附件 [AttachmentInfo]
/// </summary>
public IList Attachments {
get { return attachments; }
// set { if (value != attachments) attachments = value; }
} private ArrayList attachments = new ArrayList ();
/// <summary>
/// 发送邮件
/// </summary>
public void SendMail ()
{
// 创建TcpClient对象, 并建立连接
TcpClient tcp = null;
try
{
tcp = new TcpClient (server, port);
}
catch (Exception)
{
throw new Exception ("无法连接服务器");
} ReadString (tcp.GetStream());//获取连接信息 // 开始进行服务器认证
// 如果状态码是250则表示操作成功
if (!Command (tcp.GetStream(), "EHLO Localhost", "250"))
throw new Exception ("登陆阶段失败"); if (userName != "")
{
// 需要身份验证
if (!Command (tcp.GetStream(), "AUTH LOGIN", "334"))
throw new Exception ("身份验证阶段失败");
string nameB64 = ToBase64 (userName); // 此处将username转换为Base64码
if (!Command (tcp.GetStream(), nameB64, "334"))
throw new Exception ("身份验证阶段失败");
string passB64 = ToBase64 (password); // 此处将password转换为Base64码
if (!Command (tcp.GetStream(), passB64, "235"))
throw new Exception ("身份验证阶段失败");
}
// 准备发送
WriteString (tcp.GetStream(), "mail From: " + from);
WriteString (tcp.GetStream(), "rcpt to: " + to);
WriteString (tcp.GetStream(), "data"); // 发送邮件头
WriteString (tcp.GetStream(), "Date: " + DateTime.Now); // 时间
WriteString (tcp.GetStream(), "From: " + fromName + "<" + from + ">"); // 发件人
WriteString (tcp.GetStream(), "Subject: " + subject); // 主题
WriteString (tcp.GetStream(), "To:" + toName + "<" + to + ">"); // 收件人 //邮件格式
WriteString (tcp.GetStream(), "Content-Type: multipart/mixed; boundary=\"unique-boundary-1\"");
WriteString (tcp.GetStream(), "Reply-To:" + from); // 回复地址
WriteString (tcp.GetStream(), "X-Priority:" + priority); // 优先级
WriteString (tcp.GetStream(), "MIME-Version:1.0"); // MIME版本 // 数据ID,随意
// WriteString (tcp.GetStream(), "Message-Id: " + DateTime.Now.ToFileTime() + "@security.com");
WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding); // 内容编码
WriteString (tcp.GetStream(), "X-Mailer:JcPersonal.Utility.MailSender"); // 邮件发送者
WriteString (tcp.GetStream(), ""); WriteString (tcp.GetStream(), ToBase64 ("This is a multi-part message in MIME format."));
WriteString (tcp.GetStream(), ""); // 从此处开始进行分隔输入
WriteString (tcp.GetStream(), "--unique-boundary-1"); // 在此处定义第二个分隔符
WriteString (tcp.GetStream(), "Content-Type: multipart/alternative;Boundary=\"unique-boundary-2\"");
WriteString (tcp.GetStream(), ""); if(!isHtml)
{
// 文本信息
WriteString (tcp.GetStream(), "--unique-boundary-2");
WriteString (tcp.GetStream(), "Content-Type: text/plain;charset=" + languageEncoding);
WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding);
WriteString (tcp.GetStream(), "");
WriteString (tcp.GetStream(), body);
WriteString (tcp.GetStream(), "");//一个部分写完之后就写如空信息,分段
WriteString (tcp.GetStream(), "--unique-boundary-2--");//分隔符的结束符号,尾巴后面多了--
WriteString (tcp.GetStream(), "");
}
else
{
//html信息
WriteString (tcp.GetStream(), "--unique-boundary-2");
WriteString (tcp.GetStream(), "Content-Type: text/html;charset=" + languageEncoding);
WriteString (tcp.GetStream(), "Content-Transfer-Encoding:" + encoding);
WriteString (tcp.GetStream(), "");
WriteString (tcp.GetStream(), htmlBody);
WriteString (tcp.GetStream(), "");
WriteString (tcp.GetStream(), "--unique-boundary-2--");//分隔符的结束符号,尾巴后面多了--
WriteString (tcp.GetStream(), "");
}
// 发送附件,承上
// 对文件列表做循环
for (int i = 0; i < attachments.Count; i++)
{
WriteString (tcp.GetStream(), "--unique-boundary-1"); // 邮件内容分隔符
WriteString (tcp.GetStream(), "Content-Type: application/octet-stream;name=\"" + ((AttachmentInfo)attachments[i]).FileName + "\""); // 文件格式
WriteString (tcp.GetStream(), "Content-Transfer-Encoding: base64"); // 内容的编码
WriteString (tcp.GetStream(), "Content-Disposition:attachment;filename=\"" + ((AttachmentInfo)attachments[i]).FileName + "\""); // 文件名
WriteString (tcp.GetStream(), "");
WriteString (tcp.GetStream(), ((AttachmentInfo)attachments[i]).Bytes); // 写入文件的内容
WriteString (tcp.GetStream(), "");
} Command (tcp.GetStream(), ".", "250"); // 最后写完了,输入"." // 关闭连接
tcp.Close ();
} /// <summary>
/// 向流中写入字符
/// </summary>
/// <param name="netStream">来自TcpClient的流</param>
/// <param name="str">写入的字符</param>
protected void WriteString (NetworkStream netStream, string str)
{
str = str + "\r\n"; // 加入换行符 // 将命令行转化为byte[]
byte[] bWrite = Encoding.GetEncoding(languageEncoding).GetBytes(str.ToCharArray()); // 由于每次写入的数据大小是有限制的,那么我们将每次写入的数据长度定在75个字节,一旦命令长度超过了75,就分步写入。
int start=0;
int length=bWrite.Length;
int page=0;
int size=75;
int count=size;
try
{
if (length>75)
{
// 数据分页
if ((length/size)*size<length)
page=length/size+1;
else
page=length/size;
for (int i=0;i<page;i++)
{
start=i*size;
if (i==page-1)
count=length-(i*size);
netStream.Write(bWrite,start,count);// 将数据写入到服务器上
}
}
else
netStream.Write(bWrite,0,bWrite.Length);
}
catch(Exception)
{
// 忽略错误
}
} /// <summary>
/// 从流中读取字符
/// </summary>
/// <param name="netStream">来自TcpClient的流</param>
/// <returns>读取的字符</returns>
protected string ReadString (NetworkStream netStream)
{
string sp = null;
byte[] by = new byte[1024];
int size = netStream.Read(by,0,by.Length);// 读取数据流
if (size > 0)
{
sp = Encoding.Default.GetString(by);// 转化为String
}
return sp;
} /// <summary>
/// 发出命令并判断返回信息是否正确
/// </summary>
/// <param name="netStream">来自TcpClient的流</param>
/// <param name="command">命令</param>
/// <param name="state">正确的状态码</param>
/// <returns>是否正确</returns>
protected bool Command (NetworkStream netStream, string command, string state)
{
string sp=null;
bool success=false;
try
{
WriteString (netStream, command);// 写入命令
sp = ReadString (netStream);// 接受返回信息
if (sp.IndexOf(state) != -1)// 判断状态码是否正确
success=true;
}
catch(Exception)
{
// 忽略错误
}
return success;
} /// <summary>
/// 字符串编码为Base64
/// </summary>
/// <param name="str">字符串</param>
/// <returns>Base64编码的字符串</returns>
protected string ToBase64 (string str)
{
try
{
byte[] by = Encoding.Default.GetBytes (str.ToCharArray());
str = Convert.ToBase64String (by);
}
catch(Exception)
{
// 忽略错误
}
return str;
} /// <summary>
/// 附件信息
/// </summary>
public struct AttachmentInfo
{
/// <summary>
/// 附件的文件名 [如果输入路径,则自动转换为文件名]
/// </summary>
public string FileName {
get { return fileName; }
set { fileName = Path.GetFileName(value); }
} private string fileName; /// <summary>
/// 附件的内容 [由经Base64编码的字节组成]
/// </summary>
public string Bytes {
get { return bytes; }
set { if (value != bytes) bytes = value; }
} private string bytes; /// <summary>
/// 从流中读取附件内容并构造
/// </summary>
/// <param name="ifileName">附件的文件名</param>
/// <param name="stream">流</param>
public AttachmentInfo (string ifileName, Stream stream)
{
fileName = Path.GetFileName (ifileName);
byte[] by = new byte [stream.Length];
stream.Read (by,0,(int)stream.Length); // 读取文件内容
//格式转换
bytes = Convert.ToBase64String (by); // 转化为base64编码
} /// <summary>
/// 按照给定的字节构造附件
/// </summary>
/// <param name="ifileName">附件的文件名</param>
/// <param name="ibytes">附件的内容 [字节]</param>
public AttachmentInfo (string ifileName, byte[] ibytes)
{
fileName = Path.GetFileName (ifileName);
bytes = Convert.ToBase64String (ibytes); // 转化为base64编码
} /// <summary>
/// 从文件载入并构造
/// </summary>
/// <param name="path"></param>
public AttachmentInfo (string path)
{
fileName = Path.GetFileName (path);
FileStream file = new FileStream (path, FileMode.Open);
byte[] by = new byte [file.Length];
file.Read (by,0,(int)file.Length); // 读取文件内容
//格式转换
bytes = Convert.ToBase64String (by); // 转化为base64编码
file.Close ();
}
}
}
}