我的应用程序正在通过TCP接收命令,如果我试图比较命令比较总是失败。比较字符串总是失败(字符串从字节()转换)
消息被转换为字节()并返回,但应该在下面的示例中比较ok吗?或者我错过了什么?
Imports MyApp.Client
Public Class Form1
Public Delegate Sub MessageReceivedHandler(ByVal message As String)
Private Sub Message_Received(ByVal message As String)
'update the display using invoke
Invoke(New MessageReceivedHandler(AddressOf PrintToScreen), New Object() {message})
End Sub
Private Sub PrintToScreen(ByVal msg As String)
Select Case msg
Case "#all"
'Do Something
Case Else
'Do Something Else
End Select
End Sub
End Class
'Client class
Public Class Client
Private _tcpClient As TcpClient
Public Event MessageReceived As MessageReceivedHandler
Public Sub Connect(ByVal address As IPAddress, ByVal port As Integer)
_tcpClient = New TcpClient()
Dim serverEndPoint As New IPEndPoint(address, port)
_tcpClient.Connect(serverEndPoint)
ThreadPool.QueueUserWorkItem(New WaitCallback(AddressOf Read))
End Sub
Public Sub Send(ByVal buffer As Byte())
_tcpClient.GetStream().Write(buffer, 0, buffer.Length)
_tcpClient.GetStream().Flush()
End Sub
Private Sub Read()
Dim encoder As New ASCIIEncoding()
Dim buffer As Byte() = New Byte(4095) {}
Dim bytesRead As Integer
While True
Try
bytesRead = _tcpClient.GetStream().Read(buffer, 0, 4096)
RaiseEvent MessageReceived(encoder.GetString(buffer, 0, bytesRead).ToString)
Catch ex As IO.IOException
Application.Exit()
End Try
End While
End Sub
Public Sub Dispose()
_tcpClient.Close()
End Sub
End Class
变量是含有相同的文字的情况下的字符串,但它未能通过比较:
请问您可以将其工作到最小的可重复范例吗? – asawyer 2012-07-30 15:18:53
什么是从套接字读取的字节? ASCII编码后产生的字符串是什么?哪个字符与预期不同?正如@asawyer所说,请简化这个例子到几行代码,它们重现了根本不涉及TCP通信的问题。例如,你的例子可以简单地声明一个字节数组,用预期的硬编码值填充它,然后ascii将它编码为一个字符串,然后将它与预期的字符串进行比较。 – 2012-07-30 15:31:18
我怀疑问题根本不在于编码,而是在您确定收到完整的消息之前立即提升“MessageReceived”事件。例如,当你调用'_tcpClient.GetStream()。Read'时,它可能只返回消息的第一部分,因为这是迄今为止所收到的全部内容。 – 2012-07-30 15:47:59