我已经创建了一个TCP / IP服务器/客户端,它是异步的,但它连接了消息。我如何正确地在开始时添加标题,然后在结尾处使用字符串构建器来取消连接完整的消息。
服务器阅读消息:
Private Sub ReadCallback(ByVal result As IAsyncResult)
Try
allDone.Set()
Dim success As Boolean = result.AsyncWaitHandle.WaitOne(500, True)
If success Then
Dim client As ServerClient = TryCast(result.AsyncState, ServerClient)
If client Is Nothing Then
Return
End If
Dim networkStream As NetworkStream = client.NetworkStream
Dim read As Integer = networkStream.EndRead(result)
If read = 0 Then
SyncLock Me.Clients
Me.Clients.Remove(client.ClientID)
Return
End SyncLock
End If
If client.NetworkStream.CanRead Then
dataString.Append(Me.Encoding.GetString(client.buffer, 0, read))
networkStream.BeginRead(client.buffer, 0, client.buffer.Length, AddressOf ReadCallback, client)
allDone.WaitOne(500, True)
End If
End If
Catch ex As IO.IOException
Dim client As ServerClient = TryCast(result.AsyncState, ServerClient)
SyncLock Me.Clients
Me.Clients.Remove(client.ClientID)
Return
End SyncLock
Catch ex As Exception
If Not Me.tcpListener.Server.Connected Then
Return
End If
End Try
End Sub
客户端写信息:
Public Function Write(value As String, encoding As Encoding) As Guid
Dim buffer As Byte() = encoding.GetBytes(value)
Return Me.Write(buffer)
End Function
Public Function Write(buffer As Byte()) As Guid
Dim guid__1 As Guid = Guid.NewGuid()
Dim networkStream As NetworkStream = Me.client.GetStream()
Dim result As IAsyncResult = networkStream.BeginWrite(buffer, 0, buffer.Length, Nothing, guid__1)
result.AsyncWaitHandle.WaitOne()
networkStream.EndWrite(result)
Return guid__1
End Function
答案 0 :(得分:5)
您需要在TCP / IP之上定义(可能很简单和简单)协议,以便您知道一条消息的开始和结束位置。 TCP / IP可以并且将对您发送的消息进行分段,以便接收方可以获取消息,整个消息或多条消息的一部分。一种简单的方法是编写消息长度,然后是消息。然后接收器读入一个字节缓冲区,一旦收到适当的字节数(基于发送的长度),就可以将消息拉出并编码成一个字符串。