/// <summary>
/// UDP打洞过程
/// 假设A想连接B.首先A发送打洞消息给Server,让Server告诉B有人想与你建立通话通道,Server将A的IP信息转发给B
/// B收到命令后向A发一个UDP包,此时B的NAT会建立一个与A通讯的Session. 然后A再次向B发送UDP包B就能收到了
/// </summary>
public void HolePunching(User user)
{
//A:自己; B:参数user
//A发送打洞消息给服务器,请求与B打洞
C2S_HolePunchingRequestMessage msg = new C2S_HolePunchingRequestMessage(_LocalUserName, user.UserName);
SendMessage(msg, _hostPoint);
Thread.Sleep(2000);//等待对方发送UDP包并建立Session
//再向对方发送确认消息，如果对方收到会发送一个P2P_HolePunchingResponse确认消息，此时打洞成功
P2P_HolePunchingTestMessage confirmMessage = new P2P_HolePunchingTestMessage(_LocalUserName);
SendMessage(confirmMessage, user);
}
//运行线程
private void Run()
{
try
{
byte[] buffer;//接受数据用
while (true)
{
buffer = _client.Receive(ref _remotePoint);//_remotePoint变量返回当前连接的用户IP地址
object msgObj = ObjectSerializer.Deserialize(buffer);
Type msgType = msgObj.GetType();
DoWriteLog("接收到消息:" + msgType + " From:" + _remotePoint);
if (msgType == typeof(S2C_UserListMessage))
{
// 更新用户列表
S2C_UserListMessage usersMsg = (S2C_UserListMessage)msgObj;
_userList.Clear();
foreach (User user in usersMsg.UserList)
_userList.Add(user);
DisplayUsers(_userList);
}
else if (msgType == typeof(S2C_UserAction))
{
//用户动作，新用户登录/用户登出
S2C_UserAction msgAction = (S2C_UserAction)msgObj;
if (msgAction.Action == UserAction.Login)
{
_userList.Add(msgAction.User);
DisplayUsers(_userList);
}
else if (msgAction.Action == UserAction.Logout)
{
User user = _userList.Find(msgAction.User.UserName);
if (user != null) _userList.Remove(user);
DisplayUsers(_userList);
}
}
else if (msgType == typeof(S2C_HolePunchingMessage))
{
//接受到服务器的打洞命令
S2C_HolePunchingMessage msgHolePunching = (S2C_HolePunchingMessage)msgObj;
//NAT-B的用户给NAT-A的用户发送消息,此时UDP包肯定会被NAT-A丢弃，
//因为NAT-A上并没有A->NAT-B的合法Session, 但是现在NAT-B上就建立了有B->NAT-A的合法session了!
P2P_HolePunchingTestMessage msgTest = new P2P_HolePunchingTestMessage(_LocalUserName);
SendMessage(msgTest, msgHolePunching.RemotePoint);
}
else if (msgType == typeof(P2P_HolePunchingTestMessage))
{
//UDP打洞测试消息
//_HoleAccepted = true;
P2P_HolePunchingTestMessage msgTest = (P2P_HolePunchingTestMessage)msgObj;
UpdateConnection(msgTest.UserName, _remotePoint);
//发送确认消息
P2P_HolePunchingResponse response = new P2P_HolePunchingResponse(_LocalUserName);
SendMessage(response, _remotePoint);
}
else if (msgType == typeof(P2P_HolePunchingResponse))
{
//_HoleAccepted = true;//打洞成功
P2P_HolePunchingResponse msg = msgObj as P2P_HolePunchingResponse;
Debug.Assert(msg != null, "msg != null");
UpdateConnection(msg.UserName, _remotePoint);
}
else if (msgType == typeof(P2P_TalkMessage))
{
//用户间对话消息
P2P_TalkMessage workMsg = (P2P_TalkMessage)msgObj;
DoWriteLog(workMsg.Message);
}
else
{
DoWriteLog("收到未知消息!");
}
}
}
catch (Exception ex) { DoWriteLog(ex.Message); }
}