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StreamReader不會停止讀取C#

[英]StreamReader does not stop reading C#

我在使用Windows窗體的兩台計算機之間建立了TCP連接。 我有一個整數數組,正在使用XmlSerializer類進行序列化,並使用StreamWriter發送它,並使用StreamReader進行接收。
發送:

NetworkStream stream = m_client.GetStream();   //m_client is a TCPclient
StreamWriter m_writer = new StreamWriter(stream);
int[] a = new int[3] { 10,20,30 };
XmlSerializer serializer = new XmlSerializer(typeof(int[]));
serializer.Serialize(m_writer, a);
//m_writer.Flush();       //Doesn't help
//m_writer.Close();

在接收端:

TcpClient client = (TcpClient)p_client;
NetworkStream stream = client.GetStream();
StreamReader reader = new StreamReader(stream);
if (stream.CanRead)
{
    XmlSerializer serializer = new XmlSerializer(typeof(int[]));
    int[] numbers = (int[])serializer.Deserialize(reader);
    MessageBox.Show(numbers[0].ToString());    //Is not reached
    MessageBox.Show(numbers[1].ToString());
    MessageBox.Show(numbers[2].ToString());
}

問題在於,除非我終止連接或關閉發送方的m_writer,否則接收方的閱讀器不會停止讀取(在這種情況下,我無法將其再次用於發送)。 如果它不停止讀取,則下一行(即MessageBox.Show(numbers [0] .ToString()))將無法工作。

我需要一些建議,告訴我如何通知接收者30點后停止閱讀,或者如何理解何時停止閱讀?

編輯:
我從如何在c#中通過TCP連接發送整數數組中得到了XMLserializer的想法。
我找到了一個需要終止連接的答案,除非是唯一的方法,否則我不希望這樣做。 XmlSerializer不會通過NetworkStream反序列化

僅當底層套接字關閉時, NetworkStream才會結束。

因此,您需要盡可能多地讀取數據。 用它創建一個MemoryStream並反序列化,如鏈接的文章所示。

通過TCP發送數據時,如果字節流中有任何邊界,則由您定義和實現它們。

在您的特定示例中,可以在XML數據之前加上字節計數似乎很合理。 使用空字節終止數據也是合理的(因為XML本身絕不應該有空字節)。 兩種方法都可以,但是恕我直言,基於長度的方法稍微簡單一些(不需要緩沖額外的未處理數據)。

可能看起來像這樣:

NetworkStream stream = m_client.GetStream();   //m_client is a TCPclient
using (MemoryStream buffer = new MemoryStream())
using (StreamWriter writer = new StreamWriter(buffer))
{
    int[] a = new int[3] { 10,20,30 };
    XmlSerializer serializer = new XmlSerializer(typeof(int[]));
    serializer.Serialize(writer, a);

    // This code assumes you aren't sending more than 2GB of XML.
    // This allows the other end to use int instead of long for the
    // length to receive.
    byte[] lengthBytes = BitConverter.GetBytes((int)buffer.Length);

    stream.Write(lengthBytes, 0, lengthBytes.Length);
    buffer.Position = 0;
    buffer.CopyTo(stream);
}

然后接收:

TcpClient client = (TcpClient)p_client;
NetworkStream stream = client.GetStream();

// Using BinaryReader is easier than implementing a correct, blocking read
// of fixed numbers of bytes -- TCP can return as little as a single byte for
// any given receive operation, but BinaryReader insulates us from that.
// Leave the stream open so that we can read more later.
using (BinaryReader binary = new BinaryReader(stream, Encoding.UTF8, true))
{
    int length = binary.ReadInt32();
    byte[] buffer = binary.ReadBytes(length);

    using (MemoryStream streamBuffer = new MemoryStream(buffer))
    using (StreamReader reader = new StreamReader(streamBuffer))
    {
        XmlSerializer serializer = new XmlSerializer(typeof(int[]));
        int[] numbers = (int[])serializer.Deserialize(reader);
        MessageBox.Show(numbers[0].ToString());    //Is not reached
        MessageBox.Show(numbers[1].ToString());
        MessageBox.Show(numbers[2].ToString());
    }
}

MemoryStream一句:從技術上講,不需要using MemoryStream或根本不using MemoryStream對象。但是無論如何,我都使用using ;它為代碼增加了很少的開銷,並且使我養成了始終丟棄的習慣我創建的流)。

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