我的程序"卡在这一行"阅读流

Question

此

所以我像往常一样在读一条小溪。然后它就卡住了。它不会抛出异常或任何东西。它只是卡住了。

            Try
                Do
                    read = stream.Read(datain, 0, datain.Length) 'Stuck here
                    responseData = System.Text.Encoding.ASCII.GetString(datain, 0, read)
                    finalResponse = finalResponse + responseData
                Loop While read > 0
            Catch ex As Exception

我该怎么做才能让程序永远不会陷入困境？注意，我已经把代码放在try-catch块中了

这是完整的程序。

  Public Function getWhoisInfoAsText4(strDomainName As String, whoisServerToTry As String) As String
        'testAsisWhois()
        Dim data = System.Text.Encoding.ASCII.GetBytes(strDomainName & Microsoft.VisualBasic.vbCr & Microsoft.VisualBasic.vbLf)
        Dim finalResponse = String.Empty
        Dim client As TcpClient
        Try
            client = New TcpClient(whoisServerToTry, 43)
        Catch ex As Exception
            Return ""
        End Try
        Dim stream = client.GetStream()
        Using stream
            stream.Write(data, 0, data.Length)
            Dim datain = New Byte(254) {}
            Dim responseData = String.Empty
            Dim read As Integer
            Try
                Do
                    read = stream.Read(datain, 0, datain.Length)
                    responseData = System.Text.Encoding.ASCII.GetString(datain, 0, read)
                    finalResponse = finalResponse + responseData
                Loop While read > 0
            Catch ex As Exception
            End Try
        End Using
        If finalResponse.Contains("Name Server:") Then
            appendToTextFile(whoisServerToTry + vbNewLine, "appendfiles", Scripting.IOMode.ForAppending)
        End If
        finalResponse += (whoisServerUsed + whoisServerToTry + vbNewLine)
        Return finalResponse
    End Function

Answer 1

您的程序是否停留在第一个循环序列？

根据MSDN mabye的说法，这应该有助于

            Dim numBytesRead as Integer = 0 
            Do
                read = stream.Read(datain, numBytesRead, datain.Length)
                responseData = System.Text.Encoding.ASCII.GetString(datain, 0, read)
                finalResponse = finalResponse + responseData
                numBytesRead += read
            Loop While read > 0

Answer 2

Stream.Read总是等待，直到它期望的字节数到来，如果在程序正处于Read的那一刻通信中断，并且连接关闭，则程序将永远在这一点上等待剩余字节的到来，除非您将配置Read Timeout，否则在这段时间内没有接收到任何字节后，它将抛出异常。然后，您应该尝试捕获并重新启动连接。