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我是编程新手，我有一个无法解决的问题。我创建了一个共享文件的程序，例如 Dropbox。我有一台运行良好的服务器和一个客户端。问题是，当我尝试从服务器下载文件时，流中似乎缺少一些字节。

clientSocket = new TcpClient(Program.host, Program.port);
NetworkStream networkStream = clientSocket.GetStream();
StreamWriter write = new StreamWriter(networkStream);
write.WriteLine(need);
write.Flush();
write.WriteLine(loca);
write.Flush();
StreamReader read = new StreamReader(networkStream);
Int64 size = Convert.ToInt64(read.ReadLine());
long blocks = size / 1024;
long blocksDown = 0;
try
{
    string fileName = string.Empty;
    int qtd = 0;
    int blockSize = 1024;
    double progress = 0;
    Int64 qtdDown = 0;
    Byte[] dataByte = new Byte[blockSize];
    bool download = true;
    lock (this)
    {
        networkStream.Read(dataByte, 0, dataByte.Length);
        int fileNameLen = BitConverter.ToInt32(dataByte, 0);
        fileName = Encoding.ASCII.GetString(dataByte, 4, fileNameLen);
        if (File.Exists(Program.loc + fileName))
            switch (MessageBox.Show("Ficheiro já existente!\r\nDeseja Substituir?", "Aviso", MessageBoxButtons.YesNo,
                MessageBoxIcon.Warning))
            {
                case DialogResult.Yes:
                    File.Delete(Program.loc + fileName);
                    download = true;
                    break;
                case DialogResult.No:
                    download = false;
                    break;
            }
        if (download)
        {
            Stream fileStream = File.OpenWrite(Program.loc + fileName);
            fileStream.Write(dataByte, 4 + fileNameLen, (1024 - (4 + fileNameLen)));
            bool progChanged = false;
            backWork.WorkerReportsProgress = true;
            double progAnt = 0;
            while (true)
            {
                qtd = networkStream.Read(dataByte, 0, blockSize);
                qtdDown += qtd;
                progress = (double)qtdDown * (double)100 / (double)size;
                if (Math.Round(progress) > Math.Round(progAnt))
                {
                    progChanged = true;
                    progAnt = progress;
                }
                if (Math.Round(progress) > 0 && progChanged)
                {
                    backWork.ReportProgress(((int)Math.Round(progress)));
                    progChanged = false;
                }
                fileStream.Write(dataByte, 0, qtd);
                fileStream.Flush();
                blocksDown++;
                if (qtd == 0)
                {
                    backWork.ReportProgress(100);
                    qtd = networkStream.Read(dataByte, 0, blockSize);
                    networkStream.Close();
                    fileStream.Close();
                    break;
                }
            }
            MessageBox.Show("O ficheiro " + fileName + " foi guardado em " + Program.loc + ".", "Download",
                MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
    }
}

这就是我正在做的事情。我正在后台工作人员上进行下载。首先我在流上写下我正在做的事情，然后我打开文件的流，然后开始读取流并写入文件。

@Ňuf我试过你说的还是不行代码看起来像这样，来自qtdDown的字节和大小不相等。抱歉，如果有些部分是葡萄牙语，我的母语是葡萄牙语。

    btnAct.Enabled = false;
    btnBro.Enabled = false;
    btnDown.Enabled = false;
    btnSend.Enabled = false;
    menuStrip1.Enabled = false;
    pBar.Value = 0;
    clientSocket = new TcpClient(Program.host, Program.port);
    NetworkStream networkStream = clientSocket.GetStream();
    StreamWriter write = new StreamWriter(networkStream);
    write.WriteLine(need);
    write.Flush();
    write.WriteLine(loca);
    write.Flush();
    int blockSize = 1024;
    byte[] fileSizeBytes = new byte[blockSize];
    networkStream.Read(fileSizeBytes, 0, blockSize);
    string fileSizeString = Encoding.ASCII.GetString(fileSizeBytes, 0, fileSizeBytes.Length);
    fileSize = Convert.ToInt64(fileSizeString);
    qtdDown = 0;
    try
    {
        string fileName = string.Empty;
        int qtd = 0;
        double progress = 0;
        Byte[] dataByte = new Byte[blockSize];
        bool download = true;
        lock (this)
        {
            networkStream.Read(dataByte, 0, dataByte.Length);
            int fileNameLen = BitConverter.ToInt32(dataByte, 0);
            fileName = Encoding.ASCII.GetString(dataByte, 4, fileNameLen);
            if (File.Exists(Program.loc + fileName))
                switch (MessageBox.Show("Ficheiro já existente!\r\nDeseja Substituir?", "Aviso", MessageBoxButtons.YesNo,
                    MessageBoxIcon.Warning))
                {
                    case DialogResult.Yes:
                        File.Delete(Program.loc + fileName);
                        download = true;
                        break;
                    case DialogResult.No:
                        download = false;
                        break;
                }
            if (download)
            {
                Stream fileStream = File.OpenWrite(Program.loc + fileName);
                fileStream.Write(dataByte, 4 + fileNameLen, (1024 - (4 + fileNameLen)));
                networkStream.ReadTimeout = 60;
                backWork.WorkerReportsProgress = true;
                double progAnt = 0;
                while (true)
                {
                    qtd = networkStream.Read(dataByte, 0, blockSize);
                    qtdDown += qtd;
                    progress = (double)qtdDown * (double)100 / (double)fileSize;
                    if (Math.Round(progress) > Math.Round(progAnt))
                    {
                        progAnt = progress;
                        backWork.ReportProgress(((int)Math.Round(progress)));
                    }
                    fileStream.Write(dataByte, 0, qtd);
                    if (qtdDown == fileSize)
                    {
                        backWork.ReportProgress(100);
                        fileStream.Close();
                        networkStream.Close();
                        break;
                    }
                }
                MessageBox.Show("O ficheiro " + fileName + " foi guardado em " + Program.loc + ".", "Download",
                    MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }
    }

    catch (Exception ex)
    {
        menuStrip1.Enabled = true;
        btnAct.Enabled = true;
        btnBro.Enabled = true;
        btnDown.Enabled = true;
        btnSend.Enabled = true;
        MessageBox.Show("Ocorreu um erro!" + "\r\nBytes Downloaded: "
            + qtdDown.ToString() + "\\" + fileSize.ToString() + "\r\nDetalhes do Erro: " + ex.Message, "Download",
            MessageBoxButtons.OK, MessageBoxIcon.Error);
    }

    menuStrip1.Enabled = true;
    btnAct.Enabled = true;
    btnBro.Enabled = true;
    btnDown.Enabled = true;
    btnSend.Enabled = true;
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2 回答 2

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您通过调用 read.ReadLine() 正在丢失字节。尽管此函数仅返回一行的数据，但它在内部从网络流中读取更多数据到内部缓冲区并保留剩余数据以供后续 read.Read() 调用，这在您的代码中永远不会发生。

使用 StreamReader 读取数据或直接从 NetworkStrem 读取数据，但不要将两者的读数混合在一起。

于 2012-05-15T16:50:06.107 回答
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我在最后一个if中添加了这一行，* || (fileSize - qtdDown) < 1024* 并且文件现在可以工作，我不知道最后一个字节是否重要，但文件现在可以工作。

于 2012-05-16T09:04:35.343 回答