C# ReceiveBufferSize 显示不正确的值

Question

client.ReceiveBufferSize 没有给出正确的接收字节大小。

所以我尝试使用 client.Client.SendFile("FileName.png") 来代替，但仍然给出相同的结果。我还进行了检查以确保它发送的图像超过 64KB，并且确实显示它发送的图像超过 64KB（来自客户端）。

服务器代码：

TcpListener server = new TcpListener(IPAddress.Any,12345);
TcpClient client = server.AcceptTcpClient();
NetworkStream clientstream = client.GetStream();
                byte[] ImageByte = new byte[client.ReceiveBufferSize];
                int ReceiveCount = await clientstream.ReadAsync(ImageByte,0,ImageByte.Length);
                File.WriteAllBytes("Screenshot.png",ImageByte);

客户代码：

TcpClient client = new TcpClient();
client.Connect(IPAddress.Parse("123.456.789.123"), 12345);
                    byte[] imagebyte = File.ReadAllBytes("ImageCaptured.temp");
                    client.GetStream().Write(imagebyte, 0, imagebyte.Length);
                    File.Delete("ImageCaptured.temp");

client.ReceiveBufferSize 应该显示大约 128KB，但最多只能显示 64KB。

Answer 1

TCP 不是 "byte[] in same byte[] out" 系统。您可以将写入拆分为多个读取，甚至可以将多个写入合并为一个读取。

您需要做的是在您的代码中实现 Message Framing。这意味着您需要发送接收方可以理解的额外数据，以了解在单个 "message".

中发送了多少数据

这是一个非常简单的例子，在图片之前发送长度然后另一端读取长度然后读取该字节数。

客户代码

using(TcpClient client = new TcpClient())
{
    client.Connect(IPAddress.Parse("123.456.789.123"), 12345);
    using (var clientStream = client.GetStream()) 
    {
        int imageLength = reader.ReadInt32();
        byte[] imagebyte = new byte[imageLength);
        int readBytes = 0;
        while (readBytes < imageLength)
        {
             int nextReadSize = Math.Min(client.Available, imageLength - readBytes);
             readBytes += await clientStream.ReadAsync(imagebyte, readBytes, nextReadSize);
        }
        File.WriteAllBytes("Screenshot.png",imageByte);
    }
}

服务器代码

TcpListener server = new TcpListener(IPAddress.Any,12345);
using(TcpClient client = await server.AcceptTcpClientAsync()) 
{
    byte[] imagebyte = File.ReadAllBytes("ImageCaptured.temp");
    using(BinaryWriter writer = new BinaryWriter(client.GetStream()))
    {
        writer.Write(imagebyte.Length)
        writer.Write(imagebyte, 0, imagebyte.Length);
    }
    File.Delete("ImageCaptured.temp");
}

客户端请注意，如果您不打算关闭 TcpClient 并发送更多数据，则需要将 using(BinaryWriter writer = new BinaryWriter(client.GetStream())) 替换为 using(BinaryWriter writer = new BinaryWriter(client.GetStream(), Encoding.UTF8, true))

C# ReceiveBufferSize 显示不正确的值

C# ReceiveBufferSize shows incorrect value

c#

image

networkstream

tcpclient