一个C#文件传输模块,支持断点续传
最近做一个程序需要传送文件,在网上找了好久也没找到好用的方案,于是自己写了一个,与大家分享,希望大家帮忙改进,拍砖欢迎～
文件采取分块发送,每块单独校验,能够保证文件的完整性.同时还提供磁盘缓存功能.
经过实际测试,通过局域网(有线和WiFi)传送一个5G左右的文件取得成功.
最大缺点是CPU占用率过高,测试中发送端(939AMD3000+)达到40%,接收端(双核T9600、939AMD3200+)分别为15%和35%左右.
性能确实还有待改进....
贴出部分代码,其他的放附件里:
文件采取分块发送,每块单独校验,能够保证文件的完整性.同时还提供磁盘缓存功能.
经过实际测试,通过局域网(有线和WiFi)传送一个5G左右的文件取得成功.
最大缺点是CPU占用率过高,测试中发送端(939AMD3000+)达到40%,接收端(双核T9600、939AMD3200+)分别为15%和35%左右.
性能确实还有待改进....
贴出部分代码,其他的放附件里:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net.Sockets;
using System.Text;
using System.Threading;
namespace Takamachi660.FileTransmissionSolution
{//Version 0.6
#region CRC32算法
/// <summary>
/// CRC32快速检测算法
/// 本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/ZZJ_4Ever/archive/2009/03/31/4038551.aspx
/// 有稍作修改
/// </summary>
public static class CRC32
{
static UInt32[] crcTable = {
0x0, 0x77073096, 0xee0e612c, 0x990951ba, 0x76dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
0xedb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x9b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
0x76dc4190, 0x1db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x6b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0xf00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x86d3d2d, 0x91646c97, 0xe6635c01,
0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
0xedb88320, 0x9abfb3b6, 0x3b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x4db2615, 0x73dc1683,
0xe3630b12, 0x94643b84, 0xd6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0xa00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x26d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x5005713,
0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0xcb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0xbdbdf21,
0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
};
public static int GetCRC32(byte[] bytes)
{
int iCount = bytes.Length;
UInt32 crc = 0xFFFFFFFF;
for (int i = 0; i < iCount; i++)
{
crc = ((crc >> 8) & 0x00FFFFFF) ^ crcTable[(crc ^ bytes[i]) & 0xFF];
}
UInt32 temp = crc ^ 0xFFFFFFFF;
int t = (int)temp;
return (t);
}
}
#endregion #region 一些常量和扩展方法
/// <summary>
/// 一些常量和扩展方法
/// </summary>
public static class Consts
{
/// <summary>
/// 文件区块数据标头
/// </summary>
public const byte FileBlockHeader = 0;
/// <summary>
/// 字符串信息标头
/// </summary>
public const byte StringHeader = 1;
/// <summary>
/// 分块大小1MB
/// </summary>
public const int BlockSize = 1048576;
/// <summary>
/// 网络上传送的数据包最大大小
/// </summary>
public const int NetBlockMaxSize = BlockSize + 9;
/// <summary>
/// 默认磁盘缓存大小(单位:区块数)
/// </summary>
public const int DefaultIOBufferSize = 8;
/// <summary>
/// 空格
/// </summary>
public const string Space = " ";
/// <summary>
/// 空格替代符
/// </summary>
public const string SpaceReplacement = @"<SPACE>";
/// <summary>
/// 获取校验值
/// </summary>
/// <param name="bytes">输入数据</param>
/// <returns>输出的校验值</returns>
public static byte[] GetHash(this byte[] bytes)
{
return BitConverter.GetBytes(CRC32.GetCRC32(bytes));
}
/// <summary>
/// 比较两二进制数据内容是否完全相同(用于校验值的比较)
/// </summary>
/// <param name="THIS">数据一</param>
/// <param name="obj">数据二</param>
public static bool BytesEqual(this byte[] THIS, byte[] obj)
{
if (THIS.Length != obj.Length)
return false;
for (int index = 0; index < obj.Length; index++)
{
if (THIS[index] != obj[index])
return false;
}
return true;
}
/// <summary>
/// 将指令字符串转化为二进制数据并添加标头
/// </summary>
public static byte[] ToBytes(this string str_input)
{
byte[] strdata = Encoding.UTF8.GetBytes(str_input);
byte[] output = new byte[1 + strdata.Length];
output[0] = StringHeader;
System.Array.Copy(strdata, 0, output, 1, strdata.Length);
return output;
}
/// <summary>
/// 将二进制数据转化为指令字符串
/// </summary>
public static string ToFTString(this byte[] bytes_input)
{
if (bytes_input[0] != StringHeader)
throw new FormatException("Bad Header!");
return Encoding.UTF8.GetString(bytes_input, 1, bytes_input.Length - 1).TrimEnd('\0');
}
/// <summary>
/// 替换可能会对命令解析造成干扰的字符
/// </summary>
public static string DoReplace(this string str_input)
{
return str_input.Replace(Space, SpaceReplacement);
}
/// <summary>
/// 还原被替换的字符
/// </summary>
public static string DeReplace(this string str_input)
{
return str_input.Replace(SpaceReplacement, Space);
}
}
#endregion #region 一些委托
public delegate void BlockFinishedEventHandler(object sender, BlockFinishedEventArgs e);
public delegate void CommandReceivedEventHandler(object sender, CommandReceivedEventArgs e);
public delegate void FileTransmissionErrorOccurEventHandler(object sender,FileTransmissionErrorOccurEventArgs e);
public delegate void Delegate_SendBlocks(int Start, int End);
public delegate void Delegate_Void_Bool(bool logic);
public delegate int Delegate_Int_Int(int value);
#endregion #region 文件区块类
public class FileBlockException : Exception
{
public enum ErrorCode
{
BadHeader,
BadIndex,
IllegalFileBlockSize,
ChecksumError,
}
public ErrorCode Code { get; set; }
public FileBlockException(string message, ErrorCode ErrorCode)
: base(message)
{
Code = ErrorCode;
}
}
/// <summary>
/// 文件区块类
/// </summary>
public class FileBlock : IComparable<FileBlock>
{
/// <summary>
/// 与该区块关联的传输对象
/// </summary>
internal FileTransmission _Task;
/// <summary>
/// 与该区块关联的FileStream
/// </summary>
internal FileStream _FileStream;
/// <summary>
/// 文件数据
/// </summary>
internal byte[] _Data;
/// <summary>
/// 数据长度
/// </summary>
internal int _DataLength;
/// <summary>
/// 数据的Hash值
/// </summary>
internal byte[] _DataHash;
/// <summary>
/// 获取或设置该区块的序号(该区块在文件中的位置)
/// </summary>
public int Index { get; set; }
/// <summary>
/// 获取该区块的数据长度
/// </summary>
public int DataLength { get { return _DataLength; } }
/// <summary>
/// 获取该数据块的校验值
/// </summary>
public byte[] DataHash { get { return _DataHash; } }
/// <summary>
/// 构造函数
/// 用于从文件读入区块
/// </summary>
/// <param name="fStream">输入的文件流</param>
/// <param name="BlockIndex">分块位置</param>
/// <param name="ReadOnCreated">是否立即从文件读取数据</param>
public FileBlock(FileTransmission TransmissionTask, int BlockIndex, bool ReadOnCreated)
{
_Task = TransmissionTask;
_FileStream = _Task.FileStream;
Index = BlockIndex;
if (ReadOnCreated)
this.Read(true);
}
/// <summary>
/// 构造函数
/// 用于从二进制数据读入区块
/// </summary>
/// <param name="fStream">要保存的文件流</param>
/// <param name="ReceivedData">输入的二进制数据</param>
public FileBlock(FileTransmission TransmissionTask, byte[] ReceivedData)
{
_Task = TransmissionTask;
_FileStream = _Task.FileStream;
if (ReceivedData[0] != Consts.FileBlockHeader)
throw new FileBlockException("Bad Header!", FileBlockException.ErrorCode.BadHeader);
Index = BitConverter.ToInt32(ReceivedData, 1);
_DataLength = ReceivedData.Length - 9;
if (_DataLength > Consts.BlockSize)
throw new FileBlockException("Illegal FileBlock Size!", FileBlockException.ErrorCode.IllegalFileBlockSize);
_Data = new byte[_DataLength];
_DataHash = new byte[4];
System.Array.Copy(ReceivedData, 5, _DataHash, 0, 4);
System.Array.Copy(ReceivedData, 9, _Data, 0, _DataLength);
if (!_DataHash.BytesEqual(_Data.GetHash()))
throw new FileBlockException("Error Hash!", FileBlockException.ErrorCode.ChecksumError);
}
/// <summary>
/// 从文件读入
/// </summary>
/// <param name="CalcHashAfterRead">是否在读取后立即计算校验值</param>
/// <returns>读取块的大小</returns>
public int Read(bool CalcHashAfterRead)
{
_Data = new byte[Consts.BlockSize];
lock (_FileStream)
{
_FileStream.Position = (long)Index * (long)Consts.BlockSize;
_DataLength = _FileStream.Read(_Data, 0, Consts.BlockSize);
}
if (_Data.Length != _DataLength)
{
byte[] old = _Data;
_Data = new byte[_DataLength];
System.Array.Copy(old, _Data, _DataLength);
}
if (CalcHashAfterRead)
CalcHash();
return _DataLength;
}
/// <summary>
/// 计算校验值
/// </summary>
/// <returns>校验值</returns>
public byte[] CalcHash()
{
return _DataHash = _Data.GetHash();
}
/// <summary>
/// 将该区块写入文件
/// </summary>
public void Write()
{
lock (_FileStream)
{
_FileStream.Position = (long)Index * (long)Consts.BlockSize;
_FileStream.Write(_Data, 0, _DataLength);
}
}
/// <summary>
/// 转化为二进制数据以传输
/// </summary>
/// <returns></returns>
public byte[] GetBytes()
{
MemoryStream mStream = new MemoryStream(1 + 4 + 4 + _DataLength);
byte[] Header = new byte[1] { Consts.FileBlockHeader };
mStream.Write(Header, 0, 1);
mStream.Write(BitConverter.GetBytes(Index), 0, 4);
mStream.Write(_DataHash, 0, 4);
mStream.Write(_Data, 0, _DataLength);
return mStream.ToArray();
}
int System.IComparable<FileBlock>.CompareTo(FileBlock obj)
{
return (Index as IComparable<int>).CompareTo(obj.Index);
}
}
#endregion #region 事件参数类
public class BlockFinishedEventArgs : EventArgs
{
public int BlockIndex { get; set; }
public BlockFinishedEventArgs(int BlockIndex) { this.BlockIndex = BlockIndex; }
}
public class CommandReceivedEventArgs : EventArgs
{
public string CommandLine { get; set; }
public CommandReceivedEventArgs(string CommandLine) { this.CommandLine = CommandLine; }
}
public class FileTransmissionErrorOccurEventArgs : EventArgs
{
public Exception InnerException { get; set; }
/// <summary>
/// 指示是否继续运行
/// </summary>
public bool Continue { get; set; }
public FileTransmissionErrorOccurEventArgs(Exception innerException)
{
InnerException = innerException;
Continue = false;
}
}
#endregion #region 文件区块抽象集合类
/// <summary>
/// 文件区块的抽象集合
/// 之所以说抽象是因为该集合并不存储实际的区块(缓存区除外)
/// 而是通过一个索引器来读写文件
/// 并提供磁盘缓存
/// </summary>
public class FileBlockCollection
{
/// <summary>
/// 与该区块关联的传输对象
/// </summary>
internal FileTransmission _Task;
/// <summary>
/// 与该区块关联的FileStream
/// </summary>
internal FileStream _FileStream;
internal bool _EnabledIOBuffer;
/// <summary>
/// 磁盘缓存区
/// </summary>
internal Dictionary<int, FileBlock> _IOBuffer; public FileBlockCollection(FileTransmission TransmissionTask)
{
_Task = TransmissionTask;
_FileStream = _Task.FileStream;
_IOBufferSize = Consts.DefaultIOBufferSize;
}
/// <summary>
/// 获取或设置一个值,该值指示是否启用磁盘缓存
/// </summary>
internal bool EnabledIOBuffer
{
get { return _EnabledIOBuffer; }
set
{
_EnabledIOBuffer = value;
if (value)
_IOBuffer = new Dictionary<int, FileBlock>();
else
{
if (_Task is FileReceiver)
WriteAllBlock();
_IOBuffer = null;
}
}
}
internal int _IOBufferSize;
/// <summary>
/// 获取已接收或已发送的区块序号列表
/// </summary>
public List<int> Finished { get { return _Task._FinishedBlock; } }
/// <summary>
/// 获取已存在(Hash成功)的区块序号列表
/// </summary>
public List<int> Exist
{
get
{
if (_Task is FileReceiver)
return ((FileReceiver)_Task)._ExistBlock;
else
return null;
}
}
/// <summary>
/// 获取被丢弃的区块序号列表
/// </summary>
public List<int> Cast
{
get
{
if (_Task is FileReceiver)
return ((FileReceiver)_Task)._CastBlock;
else
return null;
}
}
/// <summary>
/// 获取总区块数
/// </summary>
public int Count { get { return _Task._TotalBlock; } }
/// <summary>
/// 获取有效区块数(已存在+已接收)
/// </summary>
public int CountValid
{
get
{
if (_Task is FileReceiver)
return _Task._FinishedBlock.Count + ((FileReceiver)_Task)._ExistBlock.Count;
else
return _Task._FinishedBlock.Count; }
}
/// <summary>
/// 将缓存中的区块全部写入磁盘
/// </summary>
/// <returns>写入的区块数量</returns>
public int WriteAllBlock()
{
if (!_EnabledIOBuffer)
return -1;
int count = 0;
lock (_IOBuffer)
{
foreach (var b in _IOBuffer)
{
b.Value.Write();
count++;
}
if (count != _IOBuffer.Count)
throw new IOException("Can not Write All FileBlocks!");
_IOBuffer.Clear();
}
return count;
}
/// <summary>
/// 读取数据以填充缓存
/// </summary>
/// <param name="StartIndex">起始区块</param>
/// <returns>读取的区块数量</returns>
public int FillIOBuffer(int StartIndex)
{
int Index;
lock (_IOBuffer)
{
_IOBuffer.Clear();
for (Index = StartIndex; _IOBuffer.Count < _IOBufferSize && Index < _Task.Blocks.Count; Index++)
{
_IOBuffer.Add(Index, new FileBlock(_Task, Index, true));
}
}
return Index - StartIndex;
}
/// <summary>
/// 异步填充缓存
/// </summary>
/// <param name="StartIndex">起始区块</param>
public IAsyncResult BeginFillIOBuffer(int StartIndex,AsyncCallback callback,object state)
{
return new Delegate_Int_Int(FillIOBuffer).BeginInvoke(StartIndex, callback, state);
}
/// <summary>
/// 写入区块
/// </summary>
/// <param name="value">区块对象</param>
public void Write(FileBlock value)
{
if (_EnabledIOBuffer)
{
if (_IOBuffer.Count >= _IOBufferSize)
WriteAllBlock();
lock (_IOBuffer)
_IOBuffer.Add(value.Index, value);
}
else
value.Write();
}
/// <summary>
/// 读取或写入区块
/// </summary>
/// <param name="BlockIndex">区块序号</param>
public FileBlock this[int BlockIndex]
{
get
{
FileBlock output;
if (_EnabledIOBuffer)
{
bool IsInBuf;
lock (_IOBuffer)
IsInBuf = _IOBuffer.TryGetValue(BlockIndex, out output);
if (IsInBuf)
return output;
else
{
output = new FileBlock(_Task, BlockIndex, true);
BeginFillIOBuffer(BlockIndex + 1, null, null);
}
}
else
output = new FileBlock(_Task, BlockIndex, true);
return output;
}
set
{
if (BlockIndex != value.Index)
throw new FileBlockException("Bad Index!", FileBlockException.ErrorCode.BadIndex);
Write(value);
}
}
}
#endregion #region 文件传输基类
public abstract class FileTransmission : IDisposable
{
internal FileStream _FileStream;
//internal readonly TransmissionMode _Mode;
/// <summary>
/// 总区块数
/// </summary>
internal int _TotalBlock;
/// <summary>
/// 最后一个区块的大小
/// </summary>
internal int _LastBlockSize;
internal List<int> _FinishedBlock;
internal byte[] ReceiveBuf;
internal Socket _Socket;
internal EventWaitHandle _WaitHandle;
internal bool _IsAlive;
internal FileBlockCollection _Blocks;
internal DateTime _StartTime;
/// <summary>
/// 上一个区块完成的时间
/// </summary>
internal DateTime _PriorBlockTime;
internal double _ByteSpeed;
/// <summary>
/// 获取或设置一个值,该值指示是否启用磁盘缓存
/// </summary>
public bool EnabledIOBuffer
{
get { return _Blocks._EnabledIOBuffer; }
set { _Blocks.EnabledIOBuffer = value; }
}
/// <summary>
/// 获取或设置磁盘缓存的大小(单位:区块数)
/// </summary>
public int IOBufferSize
{
get { return _Blocks._IOBufferSize; }
set
{
if (!_Blocks._EnabledIOBuffer)
throw new InvalidOperationException("IOBuffer is not enabled!");
_Blocks._IOBufferSize = value;
}
}
/// <summary>
/// 获取当前磁盘缓存中的区块数
/// </summary>
public int CurrentIOBufferSize
{
get
{
if (!_Blocks._EnabledIOBuffer)
return 0;
return _Blocks._IOBuffer.Count;
}
}
/// <summary>
/// 获取或设置该传输的目标连接
/// </summary>
public Socket Socket
{
get { return _Socket; }
set
{
try
{
if (value.ProtocolType != ProtocolType.Tcp)
throw new ArgumentException("Socket Protocol must be TCP", "Socket");
_Socket = value;
_Socket.ReceiveBufferSize = _Socket.SendBufferSize = Consts.NetBlockMaxSize;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
}
/// <summary>
/// 获取与此传输关联的文件流
/// </summary>
public FileStream FileStream { get { return _FileStream; } }
/// <summary>
/// 获取或设置文件路径
/// </summary>
public string FilePath { get; set; }
/// <summary>
/// 获取或设置文件名
/// </summary>
public string FileName { get; set; }
/// <summary>
/// 获取或设置文件名(包括路径)
/// </summary>
public string FullFileName
{
get
{
try
{
return FilePath.TrimEnd('\\') + "\\" + FileName;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
return null;
}
}
set
{
try
{
int i = value.LastIndexOf('\\');
if (i > 0)
FilePath = value.Substring(0, i);
else
FilePath = Environment.CurrentDirectory;
FileName = value.Substring(i + 1);
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
}
/// <summary>
/// 一个区块完成时发生
/// </summary>
public event BlockFinishedEventHandler BlockFinished;
/// <summary>
/// 全部完成时发生
/// </summary>
public event EventHandler AllFinished;
/// <summary>
/// 连接中断时发生
/// </summary>
public event EventHandler ConnectLost;
/// <summary>
/// 出现错误时发生
/// </summary>
public event FileTransmissionErrorOccurEventHandler ErrorOccurred;
/// <summary>
/// 获取一个值,该值指示传输是否正在进行
/// </summary>
public bool IsAlive { get { return _IsAlive; } }
/// <summary>
/// 获取传输开始的时间
/// </summary>
public DateTime StartTime { get { return _StartTime; } }
/// <summary>
/// 获取已用时
/// </summary>
public TimeSpan TimePast { get { return DateTime.Now - _StartTime; } }
/// <summary>
/// 获取估计剩余时间
/// </summary>
public abstract TimeSpan TimeRemaining { get; }
/// <summary>
/// 获取平均速率(区块/秒)
/// </summary>
public double BlockAverSpeed
{
get
{
return _FinishedBlock.Count / TimePast.TotalSeconds;
}
}
/// <summary>
/// 获取平均速率(字节/秒)
/// </summary>
public double ByteAverSpeed
{
get
{
return BlockAverSpeed * Consts.BlockSize;
}
}
/// <summary>
/// 获取平均速率(千字节/秒)
/// </summary>
public double KByteAverSpeed
{
get
{
return ByteAverSpeed / 1024;
}
}
/// <summary>
/// 获取瞬时速率(字节/秒)
/// </summary>
public double ByteSpeed
{
get
{
return _ByteSpeed;
}
}
/// <summary>
/// 获取瞬时速率(千字节/秒)
/// </summary>
public double KByteSpeed
{
get
{
return _ByteSpeed / 1024;
}
}
/// <summary>
/// 获取文件总长度
/// </summary>
public long TotalSize
{
get
{
return (long)(_TotalBlock - 1) * (long)Consts.BlockSize + (long)_LastBlockSize;
}
}
/// <summary>
/// 获取已完成的数据长度
/// </summary>
public abstract long FinishedSize { get; }
/// <summary>
/// 获取进度值(%)
/// </summary>
public double Progress
{
get
{
return ((double)FinishedSize / (double)TotalSize) * 100;
}
}
/// <summary>
/// 获取该传输的区块集合
/// </summary>
public FileBlockCollection Blocks { get { return _Blocks; } }
/// <summary>
/// 默认构造函数
/// </summary>
public FileTransmission()
{
_FinishedBlock = new List<int>();
_WaitHandle = new EventWaitHandle(false, EventResetMode.ManualReset);
_Blocks = new FileBlockCollection(this);
}
/// <summary>
/// 构造函数
/// </summary>
/// <param name="FilePath">文件路径</param>
/// <param name="FileName">文件名</param>
public FileTransmission(string FilePath, string FileName)
{
_FinishedBlock = new List<int>();
_WaitHandle = new EventWaitHandle(true, EventResetMode.ManualReset);
_Blocks = new FileBlockCollection(this); this.FilePath = FilePath;
this.FileName = FileName;
}
/// <summary>
/// 初始化接收缓存
/// </summary>
internal void InitializeReceiveBuf()
{
try
{
ReceiveBuf = new byte[_Socket.ReceiveBufferSize];
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
/// <summary>
/// 开始异步接收
/// </summary>
internal abstract IAsyncResult BeginReceive();
/// <summary>
/// 开始传输
/// </summary>
public virtual void Start()
{
try
{
_IsAlive = true;
_StartTime = DateTime.Now;
_WaitHandle.Reset();
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
/// <summary>
/// 中止传输
/// </summary>
/// <param name="ShutDownSocket">是否关闭Socket</param>
public virtual void Stop(bool ShutDownSocket)
{
try
{
_IsAlive = false;
_FileStream.Close();
_FileStream = null;
_WaitHandle.Set();
if (ShutDownSocket)
{
_Socket.Shutdown(SocketShutdown.Both);
_Socket.Close();
}
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
/// <summary>
/// 异步中止传输,不关闭Socket
/// </summary>
internal void Stop()
{
new Delegate_Void_Bool(Stop).BeginInvoke(false, null, null);
}
/// <summary>
/// 等待传输完成
/// </summary>
public bool WaitForExit()
{
return _WaitHandle.WaitOne();
}
/// <summary>
/// 等待传输完成
/// </summary>
public bool WaitForExit(int millisecondsTimeout, bool exitContext)
{
return _WaitHandle.WaitOne(millisecondsTimeout, exitContext);
}
/// <summary>
/// 等待传输完成
/// </summary>
public bool WaitForExit(TimeSpan timeout, bool exitContext)
{
return _WaitHandle.WaitOne(timeout, exitContext);
}
internal virtual void OnBlockFinished(int BlockIndex)
{
if (!_FinishedBlock.Exists(a => a == BlockIndex))
_FinishedBlock.Add(BlockIndex);
if (BlockIndex == _TotalBlock - 1)
_ByteSpeed = _LastBlockSize / (DateTime.Now - _PriorBlockTime).TotalSeconds;
else
_ByteSpeed = Consts.BlockSize / (DateTime.Now - _PriorBlockTime).TotalSeconds;
_PriorBlockTime = DateTime.Now;
if (BlockFinished != null)
BlockFinished(this, new BlockFinishedEventArgs(BlockIndex));
}
internal virtual void OnConnectLost()
{
if (!_IsAlive)
return;
Stop();
if (ConnectLost != null)
ConnectLost(this, new EventArgs());
}
/// <summary>
/// 同步发送字符串
/// </summary>
public int SendString(string str)
{
try
{
return _Socket.EndSend(BeginSendString(str, null, null));
}
catch (SocketException)
{
OnConnectLost();
return 0;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
return 0;
}
}
/// <summary>
/// 异步发送字符串并使用默认的回调方法
/// </summary>
public void SendStringAsync(string str)
{
BeginSendString(str, SendCallback, null);
}
/// <summary>
/// 异步发送字符串并使用指定的的回调方法和参数
/// </summary>
public IAsyncResult BeginSendString(string str, AsyncCallback callback, object state)
{
try
{
if (!_IsAlive)
throw new InvalidOperationException("Is Not Alive");
byte[] ToSend = str.ToBytes();
return _Socket.BeginSend(ToSend, 0, ToSend.Length, SocketFlags.None, callback, state);
}
catch (SocketException)
{
OnConnectLost();
return null;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
return null;
}
}
internal void SendCallback(IAsyncResult ar)
{
try
{
_Socket.EndSend(ar);
}
catch (SocketException)
{
OnConnectLost();
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
if (ar.AsyncState != null)
{
if (ar.AsyncState is int)
{
OnBlockFinished((int)ar.AsyncState);
}
}
}
internal virtual void OnAllFinished()
{
if (AllFinished != null)
AllFinished(this, new EventArgs());
}
internal virtual void OnErrorOccurred(Exception innerException)
{
FileTransmissionErrorOccurEventArgs eventargs = new FileTransmissionErrorOccurEventArgs(innerException);
if (ErrorOccurred != null)
ErrorOccurred(this, eventargs);
if (!eventargs.Continue)
throw innerException;
}
void System.IDisposable.Dispose()
{
_FileStream.Close();
_Socket.Close();
}
}
#endregion #region 发送端类
/// <summary>
/// 发送端
/// 传输前发送端创建该类实例
/// 设置必要属性后
/// 调用Start()方法开始传输
/// </summary>
public class FileSender : FileTransmission
{
/// <summary>
/// 接收到命令时发生
/// </summary>
public event CommandReceivedEventHandler CommandReceived;
/// <summary>
/// 开始异步接收
/// </summary>
internal override IAsyncResult BeginReceive()
{
InitializeReceiveBuf();
try
{
return _Socket.BeginReceive(ReceiveBuf, 0, ReceiveBuf.Length, SocketFlags.None, ReceiveCallback, null);
}
catch (SocketException)
{
OnConnectLost();
return null;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
return null;
}
}
/// <summary>
/// 开始传输
/// </summary>
public override void Start()
{
base.Start();
try
{
BeginReceive();
_FileStream = new FileStream(FullFileName, FileMode.Open, FileAccess.Read, FileShare.Read);
_TotalBlock = (int)(_FileStream.Length / (long)Consts.BlockSize) + 1;
_LastBlockSize = (int)(_FileStream.Length - ((long)_TotalBlock - 1) * (long)Consts.BlockSize);
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
/// <summary>
/// 获取估计剩余时间
/// </summary>
public override TimeSpan TimeRemaining
{
get
{
int BlockRemaining = _TotalBlock - _FinishedBlock.Count;
return TimeSpan.FromSeconds(BlockRemaining / BlockAverSpeed);
}
}
/// <summary>
/// 获取已完成的数据长度
/// </summary>
public override long FinishedSize
{
get
{
return (long)_FinishedBlock.Count * (long)Consts.BlockSize;
}
}
/// <summary>
/// 同步发送区块
/// </summary>
/// <param name="BlockIndex">区块序号</param>
/// <returns>发送的数据长度</returns>
public int SendBlock(int BlockIndex)
{
try
{
int ret = _Socket.EndSend(BeginSendBlock(BlockIndex, null, null));
OnBlockFinished(BlockIndex);
return ret;
}
catch (SocketException)
{
OnConnectLost();
return 0;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
return 0;
}
}
/// <summary>
/// 异步发送区块并使用默认的回调方法
/// </summary>
/// <param name="BlockIndex">区块序号</param>
public void SendBlockAsync(int BlockIndex)
{
BeginSendBlock(BlockIndex, SendCallback, BlockIndex);
}
/// <summary>
/// 异步发送区块并使用指定的回调方法和参数
/// </summary>
/// <param name="BlockIndex">区块序号</param>
public IAsyncResult BeginSendBlock(int BlockIndex, AsyncCallback callback, object state)
{
try
{
if (!_IsAlive)
throw new InvalidOperationException("Is Not Alive");
if (BlockIndex >= _TotalBlock)
throw new ArgumentOutOfRangeException("BlockIndex");
byte[] ToSend = _Blocks[BlockIndex].GetBytes();
return _Socket.BeginSend(ToSend, 0, ToSend.Length, SocketFlags.None, callback, state);
}
catch (SocketException)
{
OnConnectLost();
return null;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
return null;
}
}
internal void ReceiveCallback(IAsyncResult ar)
{
bool ContinueReceive = true;
int count = 0;
try
{
count = _Socket.EndReceive(ar);
}
catch (SocketException)
{
OnConnectLost();
return;
}
catch (Exception ex)
{
try
{
OnErrorOccurred(ex);
}
catch { return; }
}
try
{
if (count == 0)
return;
switch (ReceiveBuf[0])
{
case Consts.StringHeader:
ContinueReceive = OnCommandReceived(ReceiveBuf.ToFTString());
break;
default:
throw new FormatException("Bad Header!");
}
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
if (ContinueReceive)
{
BeginReceive();
}
}
/// <summary>
/// 命令处理
/// </summary>
/// <param name="str">收到的命令</param>
/// <returns>是否继续接收</returns>
internal bool OnCommandReceived(string str)
{
if (CommandReceived != null)
CommandReceived(this, new CommandReceivedEventArgs(str));
bool ContinueReceive = true;
string[] Msg = str.Split(' ');
if (Msg[0] == "Exit")
{
OnAllFinished();
ContinueReceive = false;
Stop();
}
else if (Msg[0] == "GET")
{
if (Msg[1] == "FileBlock")
{
int BlockIndex;
if (!int.TryParse(Msg[2], out BlockIndex))
throw new FormatException("Bad BlockIndex " + Msg[2]);
SendBlock(BlockIndex);
}
else if (Msg[1] == "BlockHash")
{
int BlockIndex;
if (!int.TryParse(Msg[2], out BlockIndex))
throw new FormatException("Bad BlockIndex " + Msg[2]);
byte[] hash = _Blocks[BlockIndex].DataHash;
SendStringAsync(string.Format("BlockHash {0} {1}", BlockIndex, BitConverter.ToInt32(hash, 0)));
}
else if (Msg[1] == "FileName")
{
SendStringAsync(string.Format("SET FileName {0}", FileName.DoReplace()));
}
else if (Msg[1] == "TotalBlock")
{
SendStringAsync(string.Format("SET TotalBlock {0}", _TotalBlock));
}
else if (Msg[1] == "LastBlockSize")
{
SendStringAsync(string.Format("SET LastBlockSize {0}", _LastBlockSize));
}
else
throw new FormatException("Bad Command " + Msg[1]);
}
else
throw new FormatException("Bad Command " + Msg[0]); return ContinueReceive;
}
}
#endregion #region 接收端类
/// <summary>
/// 接收端
/// 传输前接收端创建该类实例
/// 设置必要属性后
/// 调用Start()方法开始传输
/// </summary>
public class FileReceiver : FileTransmission
{
internal List<int> _ExistBlock;
internal List<int> _CastBlock;
/// <summary>
/// 下载线程
/// </summary>
internal Thread _DownThread;
public event BlockFinishedEventHandler BlockHashed;
/// <summary>
/// 开始异步接收
/// </summary>
internal override IAsyncResult BeginReceive()
{
InitializeReceiveBuf();
try
{
return _Socket.BeginReceive(ReceiveBuf, 0, ReceiveBuf.Length, SocketFlags.None, null, null);
}
catch (SocketException)
{
OnConnectLost();
return null;
}
catch (Exception ex)
{
OnErrorOccurred(ex);
return null;
}
}
/// <summary>
/// 获取估计剩余时间
/// </summary>
public override TimeSpan TimeRemaining
{
get
{
int BlockRemaining = _TotalBlock - _FinishedBlock.Count - ((FileReceiver)this)._ExistBlock.Count;
return TimeSpan.FromSeconds(BlockRemaining / BlockAverSpeed);
}
}
/// <summary>
/// 获取已完成的数据长度
/// </summary>
public override long FinishedSize
{
get
{
return ((long)_FinishedBlock.Count + (long)_ExistBlock.Count - 1) * (long)Consts.BlockSize + (long)_LastBlockSize;
}
}
/// <summary>
/// 开始传输
/// </summary>
public override void Start()
{
base.Start();
try
{
_CastBlock = new List<int>();
_ExistBlock = new List<int>();
_DownThread = new Thread(DownLoad);
_DownThread.IsBackground = true;
_DownThread.Name = "DownThread";
_DownThread.Start();
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
/// <summary>
/// 中止传输
/// </summary>
/// <param name="ShutDownSocket">是否关闭Socket</param>
public override void Stop(bool ShutDownSocket)
{
try
{
if (_DownThread != null)
{
if ((_DownThread.ThreadState & ThreadState.Running) == ThreadState.Running)
_DownThread.Abort();
}
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
base.Stop(ShutDownSocket);
}
internal string ReceiveString()
{
int count = 0;
try
{
count = _Socket.EndReceive(BeginReceive());
}
catch (Exception ex)
{
OnConnectLost();
throw ex;
}
if (count == 0)
return null;
else
return ReceiveBuf.ToFTString();
}
internal FileBlock ReceiveFileBlock()
{
MemoryStream mStream = new MemoryStream();
while (true)
{
int count = 0;
try
{
count = _Socket.EndReceive(BeginReceive());
if (count == 0) throw new Exception();
}
catch (Exception ex)
{
OnConnectLost();
throw ex;
}
mStream.Write(ReceiveBuf, 0, count);
try
{//接收到正确的区块则返回
return new FileBlock(this, mStream.ToArray());
}
catch (FileBlockException ex)
{//接收到不完整或错误的区块,若不完整则继续接收
if (mStream.Length >= Consts.NetBlockMaxSize)
throw ex;//区块已达到指定大小但仍然错误,则抛出错误
}
}
}
/// <summary>
/// 从发送端获取文件名
/// </summary>
public void GetFileName()
{
while (true)
{
SendString("GET FileName");
string[] Msg = ReceiveString().Split(' ');
if (Msg[0] == "SET" && Msg[1] == "FileName")
{
FileName = Msg[2];
break;
}
}
}
/// <summary>
/// 从发送端获取区块总数
/// </summary>
public void GetTotalBlock()
{
while (true)
{
SendString("GET TotalBlock");
string[] Msg = ReceiveString().Split(' ');
if (Msg[0] == "SET" && Msg[1] == "TotalBlock")
{
if (int.TryParse(Msg[2], out _TotalBlock))
break;
}
}
}
/// <summary>
/// 从发送端获取最后一个区块的大小
/// </summary>
public void GetLastBlockSize()
{
while (true)
{
SendString("GET LastBlockSize");
string[] Msg = ReceiveString().Split(' ');
if (Msg[0] == "SET" && Msg[1] == "LastBlockSize")
{
if (int.TryParse(Msg[2], out _LastBlockSize))
break;
}
}
}
/// <summary>
/// 校验文件
/// </summary>
/// <returns>损坏或尚未下载的区块序号列表</returns>
public List<int> HashFile()
{
_FileStream.Position = 0;
_ExistBlock.Clear();
for (int count = 0; _FileStream.Position < _FileStream.Length && count < _TotalBlock; count++)
{//校验已存在的区块
FileBlock TestBlock = new FileBlock(this, count, true);
SendString(string.Format("GET BlockHash {0}", count));
string[] Msg = ReceiveString().Split(' ');
if (Msg[0] == "BlockHash")
{
if (Convert.ToInt32(Msg[1]) == count)
{
if (BitConverter.ToInt32(TestBlock.DataHash, 0) == Convert.ToInt32(Msg[2]))
_ExistBlock.Add(count);
}
}
if (BlockHashed != null)
BlockHashed(this, new BlockFinishedEventArgs(count));
}
int MaxExistBlockIndex;//已存在的区块最大序号
try
{
MaxExistBlockIndex = _ExistBlock.Max();
}
catch
{
MaxExistBlockIndex = 0;
}
List<int> BlockRemaining = new List<int>();
for (int index = 0; index < _TotalBlock; )
{//计算仍需传输的区块
if (index <= MaxExistBlockIndex)
{
if (_ExistBlock.Exists(a => a == index))
{
index++;
continue;
}
}
BlockRemaining.Add(index++);
}
return BlockRemaining;
}
/// <summary>
/// 接收整个文件
/// </summary>
internal void DownLoad()
{
try
{
if (string.IsNullOrEmpty(FilePath))//未指定路径时默认为接收程序所在路径
FilePath = Environment.CurrentDirectory;
if (string.IsNullOrEmpty(FileName))//未指定文件名时从发送端获取
{
GetFileName();
}
_FileStream = new FileStream(FullFileName, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None);//temp
GetTotalBlock();
GetLastBlockSize();
List<int> BlockRemaining = HashFile();
if (_FileStream.Length > TotalSize)//如果已存在的文件比目标文件长则截断它
_FileStream.SetLength(TotalSize);
_StartTime = DateTime.Now;
foreach (int index in BlockRemaining)
{
FileBlock Block;
while (true)
{
SendString(string.Format("GET FileBlock {0}", index));
try
{
Block = ReceiveFileBlock();
break;
}
catch (FileBlockException)
{//接收到错误的区块,抛弃该数据并重新请求
_CastBlock.Add(index);
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
while (true)
{
try
{
_Blocks[index] = Block;//写入区块
OnBlockFinished(index);
break;
}
catch (IOException ex)
{//磁盘写入错误时
try
{
OnErrorOccurred(ex);
//重试
}
catch
{//退出
Stop();
return;
}
}
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
}
SendStringAsync("Exit");
_Blocks.WriteAllBlock();
OnAllFinished();
Stop();
}
catch (SocketException) { }
catch (Exception ex)
{
OnErrorOccurred(ex);
}
}
}
#endregion
}
VS2008完整项目文件,包括类库和一个简单的Demo:
/Files/takamachi660/SendFileTest_v0.6.rar
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