Question

我有一台服务器可以向请求它们的客户端发送文件。对于大小小于2演出的文件，它的效果非常好。但是，当文件超过2演出时，我的服务器会在 Dim buffer 处给我一个溢出错误。我找了它，发现缓冲区大小可能是（upload.SendBufferSize -1）。但是，更改此项会给我一个不同的错误： Upload.Send ：无法立即完成非阻塞套接字操作。

我从互联网上搜索过，一个建议是尝试添加Upload.Blocking = True如果发生错误，但后来我收到一个错误，说明参数无效。

对我的问题有任何建议吗？

Private Sub UploaderAccept(ar As IAsyncResult)
    Dim File As IO.FileInfo = ar.AsyncState
    Dim Upload As Socket = UploadServer.EndAccept(ar)

    '--- Determine size of buffer
    Dim fs As New IO.FileStream(File.FullName, FileMode.Open, FileAccess.Read, FileShare.Read)
    Dim buffer(Upload.SendBufferSize - 1) As Byte
    Dim Sent As Long = 0
    Dim t As Long = 0

    '--- Actual sending
    Do Until Sent >= File.Length
        t = fs.Read(buffer, 0, buffer.Length)
        Upload.Send(buffer, 0, t, SocketFlags.None)

        Sent += t
    Loop

    '--- File transfer done
    fs.Close()

    Upload.BeginDisconnect(False, New AsyncCallback(AddressOf OnDisconnect), upload)
    Upload.Close()
End Sub

Answer 1

好吧，我自己得到了，如果有人需要它，你不能通过从异步变为同步来做到这一点。只需使用：

Upload.BeginSend（buffer，0，t，SocketFlags.None，New AsyncCallback（AddressOf OnSend），Upload）：

    Do Until Sent >= File.Length
        t = fs.Read(buffer, 0, buffer.Length)
        If t > 0 Then
            Upload.BeginSend(buffer, 0, t, SocketFlags.None, New AsyncCallback(AddressOf UploadOnSend), Upload)
        End If

        Sent += t
        TextUpdate(lblFilePerc, Sent)
    Loop
    Close streams...

Private Sub UploadOnSend(ar As IAsyncResult)
    Dim upload As Socket = ar.AsyncState
    upload.EndSend(ar)

End Sub

VB Socket.Send返回＆＃34;无法立即完成非阻塞套接字操作。＆＃34;

1 个答案: