我正在苦苦寻找一种最佳方法来实现具有强大超时管理的命名管道IPC。我不是指在建立连接时的超时,而是指在读/写流上的超时。
我找到的所有示例都没有超时实现。
是否有人能够给我提供一个可行的示例和/或指向展示此功能的示例?
NamedPipeClientStream.BeginRead
和NamedPipeClientStream.BeginWrite
进行异步读写操作;然后使用定时器来检测在一段时间内未发送或接收到数据的情况。DateTime
字段为DateTime.Now
,并且每次执行定时器时都会检查该字段以确定是否发生超时。如果超时,则可以关闭NamedPipeClientStream
,并捕获NamedPipeClientStream.EndRead
和NamedPipeClientStream.EndWrite
引发的异常。IDisposable
并添加写入方法。这应该有助于说明这个想法,但最好将此代码用作模型,而不是直接使用它。我已经测试了该代码以查看是否读取。//this is a very rough model of how to do it. a lot more would need to be implemented
//i'm assuming you plan to continuously read from it. i can think up another example if you're not
//also not thread safe
public class MyPipeClient
{
NamedPipeClientStream PipeClient = new NamedPipeClientStream("testpipe1");
Timer TimeoutTimer;
DateTime LastRead;
const int TimeoutSeconds = 120; //2 mins
//will connect and start receiving
public void Connect()
{
PipeClient.Connect();
LastRead = DateTime.Now;
TimeoutTimer = new Timer(TimeoutCheck, this, 0, 1000); //check every second
Read(this);
}
public void Disconnect()
{
PipeClient.Close(); PipeClient = null;
TimeoutTimer.Dispose(); TimeoutTimer = null;
}
static void Read(MyPipeClient client)
{
PipeState state = new PipeState(client);
try
{
client.PipeClient.BeginRead(state.Buffer, 0, state.Buffer.Length, ReadCallback, state);
}
catch (InvalidOperationException) //disconnected/disposed
{
return;
}
}
static void ReadCallback(IAsyncResult ar)
{
PipeState state = (PipeState)ar.AsyncState;
MyPipeClient client = state.Client;
client.LastRead = DateTime.Now;
int bytesRead;
try
{
bytesRead = client.PipeClient.EndRead(ar);
}
catch (IOException) //closed
{
return;
}
if (bytesRead > 0)
{
byte[] data = state.Buffer;
//TODO: something
}
else //i've never used pipes, so i'm assuming this behavior exists with them
{
client.Disconnect();
return;
}
Read(client);
}
static void TimeoutCheck(object state)
{
MyPipeClient client = (MyPipeClient)state;
TimeSpan timeSinceLastRead = DateTime.Now - client.LastRead;
if (timeSinceLastRead.TotalSeconds > TimeoutSeconds)
{
client.Disconnect();
}
}
}
class PipeState
{
public byte[] Buffer = new byte[4096];
public MyPipeClient Client;
public PipeState(MyPipeClient client)
{
Client = client;
}
}