TcpListener：检测客户端断开连接，而不是客户端暂时不发送任何数据(TcpListener: Detecting a client disconnect as opposed to a client not sending any data for a while)

 我正在寻找在使用TcpListener时如何检测“客户端断开连接”。 
 
 所有答案似乎都与此类似： TcpListener：如何检测客户端断开连接？ 
 
 基本上，从流中读取，如果Read（）返回0，则客户端已断开连接。 
 
 但这是假设客户端在发送的每个数据流之后断开连接。 我们在TCP连接/断开开销既缓慢又昂贵的环境中运行。 
 
 我们建立连接然后发送一些请求。 
 
 伪代码： 
 
client.Connect();
client.GetStatus();
client.DoSomething();
client.DoSomethingElse();
client.AndSoOn();
client.Disconnect();
 
 Connect和Disconnect（）之间的每次调用都会向服务器发送数据流。 服务器知道如何分析和处理流。 
 
 如果让TcpListener在没有断开连接的情况下读取循环，则会读取并处理所有消息，但在客户端断开连接后，服务器无法知道它并且它永远不会释放客户端并接受新客户端。 
 
var read = client.GetStream().Read(buffer, 0, buffer.Length);

if (read > 0) 
{
   //Process
}
 
 如果我让TcpListener在读取== 0时删除客户端，它只接受第一个数据流，只是在之后立即丢弃客户端。 
 
 当然这意味着新客户可以连接。 
 
 呼叫之间没有人为的延迟，但就计算机时间而言，两次呼叫之间的时间当然是“巨大的”，因此总会有一段时间读取== 0，即使这并不意味着客户端已经或应该断开连接。 
 
var read = client.GetStream().Read(buffer, 0, buffer.Length);

if (read > 0) 
{
   //Process
}
else
{
   break;   //Always executed as soon as the first stream of data has been received
}
 
 所以我想知道...有没有更好的方法来检测客户端是否已断开连接？ 

I was looking how to detect a 'client disconnect' when using a TcpListener.
 
All the answers seem to be similar to this one: TcpListener: How can I detect a client disconnect?
 
Basically, read from the stream and if Read() returns 0 the client had disconnected.
 
But that's assuming that a client disconnects after every single stream of data it sent. We operate in environments where the TCP connect/disconnect overhead is both slow and expensive.
 
We establish a connection and then we send a number of requests.
 
Pseudocode:
 
client.Connect();
client.GetStatus();
client.DoSomething();
client.DoSomethingElse();
client.AndSoOn();
client.Disconnect();
 
Each call between Connect and Disconnect() sends a stream of data to the server. The server knows how to analyze and process the streams.
 
If let the TcpListener read in a loop without ever disconnecting it reads and handles all the messages, but after the client disconnects, the server has no way of knowing that and it will never release the client and accept new ones.
 
var read = client.GetStream().Read(buffer, 0, buffer.Length);

if (read > 0) 
{
   //Process
}
 
If I let the TcpListener drop the client when read == 0 it only accepts the first stream of data only to drop the client immediately after.
 
Of course this means new clients can connect.
 
There is no artificial delay between the calls, but in terms of computer time the time between two calls is 'huge' of course, so there will always be a time when read == 0 even though that does not mean the client has or should be disconnected.
 
var read = client.GetStream().Read(buffer, 0, buffer.Length);

if (read > 0) 
{
   //Process
}
else
{
   break;   //Always executed as soon as the first stream of data has been received
}
 
So I'm wondering... is there a better way to detect if the client has disconnected?

原文：https://stackoverflow.com/questions/11662598