拆包组包提炼于一位大拿的文章，这里提供链接：
c#中关于udp实现可靠地传输(数据包的分组发送)
仅仅使用了大拿所设计的包的拆分、组装与序列化部分。
在此工程中，将拆包组包模块单独作为了一个library工程，包含了PacketHelper文件。
其中包序列化和反序列化类如下：
public class SerializationUnit { public static byte[] SerializeObject(object obj) { if (obj == null) return null; MemoryStream ms = new MemoryStream(); BinaryFormatter formatter = new BinaryFormatter(); formatter.Serialize(ms, obj); ms.Position = 0; byte[] bytes = ms.GetBuffer(); ms.Read(bytes, 0, bytes.Length); ms.Close(); return bytes; } public static object DeserializeObject(byte[] bytes) { object obj = null; if (bytes == null) return obj; MemoryStream ms = new MemoryStream(bytes); ms.Position = 0; BinaryFormatter formatter = new BinaryFormatter(); obj = formatter.Deserialize(ms); ms.Close(); return obj; } }屏幕数据包设计如下，在项目中屏幕广播的接收端并不是C#所写，在此进行了提炼，省去了其他的包体信息等：
[Serializable] public class CastPacket { public double TimeStamp { get; set; } public Int32 Index { get; set; } public Int32 Total { get; set; } public Int32 TotalLength { get; set; } public Int32 DataOffset { get; set; } public Int32 DataLength { get; set; } public byte[] Data { get; set; } public CastPacket(double timeStamp, Int32 total, Int32 index, byte[] data, Int32 dataOffset, Int32 totalLength) { this.TimeStamp = timeStamp; this.Total = total; this.Index = index; this.Data = data; this.DataOffset = dataOffset; this.DataLength = data.Length; this.TotalLength = totalLength; } public byte[] ToArray() { return SerializationUnit.SerializeObject(this); } } 拆包类为： public class PacketSplitter { public static ICollection<CastPacket> Split(double TimeStamp, byte[] data, int chunkLength = 8174) { List<CastPacket> packets = new List<CastPacket>(); int chunks = data.Length / chunkLength; int remainder = data.Length % chunkLength; int total = chunks; if (remainder > 0) total++; for (int i = 1; i <= chunks; i++) { byte[] chunk = new byte[chunkLength]; Buffer.BlockCopy(data, (i - 1) * chunkLength, chunk, 0, chunkLength); packets.Add(new CastPacket(TimeStamp, total, i, chunk, chunkLength * (i - 1), data.Length)); } if (remainder > 0) { int length = data.Length - (chunkLength * chunks); byte[] chunk = new byte[length]; Buffer.BlockCopy(data, chunkLength * chunks, chunk, 0, length); packets.Add(new CastPacket(TimeStamp, total, total, chunk, chunkLength * chunks, data.Length)); } return packets; } } 组包事件和组包类为： public class PacketCollectorEventArgs : EventArgs { public byte[] data; } public class PacketCollector { private Object ObjLock = new Object(); public EventHandler<PacketCollectorEventArgs> OnCollectorEventHandler; private Dictionary<double, List<CastPacket>> DicCollectedPacket = new Dictionary<double, List<CastPacket>>(); private double CurrentTimeStamp = -1; private Thread CollectThreadHandler; private Boolean bRunning; public PacketCollector() { bRunning = true; CollectThreadHandler = new Thread(new ThreadStart(CollectThread)) { IsBackground = true }; CollectThreadHandler.Start(); } public void Dispose() { bRunning = false; //WinHelper.WaitForThreadExit(CollectThreadHandler); DicCollectedPacket = null; } private void CollectThread() { while (bRunning == true) { lock (ObjLock) { if (DicCollectedPacket.Count == 0) continue; var SortedDic = DicCollectedPacket.OrderBy(p => p.Key).ToDictionary(p => p.Key, p => p.Value); foreach (var ListPack in SortedDic) { if (CurrentTimeStamp - ListPack.Key >= 2000) { //Console.WriteLine("Abbanded package."); DicCollectedPacket.Remove(ListPack.Key); continue; } if (ListPack.Value.Count == ListPack.Value[0].Total) { RePackMsg(ListPack.Value); DicCollectedPacket.Remove(ListPack.Key); } } } Thread.Sleep(5); } } public void Collect(Byte[] Msg) { CastPacket Pac = (CastPacket)SerializationUnit.DeserializeObject(Msg); if (Pac == null) return; if (Pac.Data == null) return; lock (ObjLock) { List<CastPacket> ListPacket = null; Boolean bContain = DicCollectedPacket.TryGetValue(Pac.TimeStamp, out ListPacket); if (bContain == false) { ListPacket = new List<CastPacket>(); ListPacket.Add(Pac); DicCollectedPacket.Add(Pac.TimeStamp, ListPacket); } else { ListPacket.Add(Pac); } CurrentTimeStamp = Math.Max(Pac.TimeStamp, CurrentTimeStamp); } } private void RePackMsg(List<CastPacket> listPack) { Byte[] Data = new Byte[listPack[0].TotalLength]; foreach (var Pac in listPack) { try { Buffer.BlockCopy(Pac.Data, 0, Data, Pac.DataOffset, Pac.Data.Length); } catch { Console.WriteLine("Wrong package."); return; } } if (this.OnCollectorEventHandler != null) this.OnCollectorEventHandler(this, new PacketCollectorEventArgs() { data = Data }); } }以上即为拆包组包所用到的共用模块，很奇怪的一点是，我把这个类分别放在客户端和服务端中会报出转换异常，还没找到原因。
源码传送门：
C#屏幕广播源码V1.0
