创建一个中间流,您可以使用它来断开 XmlWriter 与基本流的连接。
这不是最优雅的解决方案,下面的代码需要工作,因此在将其投入生产之前对其进行测试,但这是关于想法的。
public class DummyStream : Stream
{
public DummyStream(Stream baseStream)
{
if (baseStream == null)
throw new ArgumentNullException("baseStream");
BaseStream = baseStream;
}
public Stream BaseStream { get; private set; }
public void DisconnectBaseStream()
{
BaseStream = null;
}
private Stream GetBaseStream()
{
return BaseStream ?? Stream.Null;
}
public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback callback, object state)
{
return GetBaseStream().BeginRead(buffer, offset, count, callback, state);
}
public override IAsyncResult BeginWrite(byte[] buffer, int offset, int count, AsyncCallback callback, object state)
{
return GetBaseStream().BeginWrite(buffer, offset, count, callback, state);
}
public override bool CanRead
{
get { return GetBaseStream().CanRead; }
}
public override bool CanSeek
{
get { return GetBaseStream().CanSeek; }
}
public override bool CanTimeout
{
get { return GetBaseStream().CanTimeout; }
}
public override bool CanWrite
{
get { return GetBaseStream().CanWrite; }
}
public override void Close()
{
// We do not close the BaseStream because this stream
// is just a wrapper.
// GetBaseStream().Close();
}
public override ObjRef CreateObjRef(Type requestedType)
{
return GetBaseStream().CreateObjRef(requestedType);
}
protected override void Dispose(bool disposing)
{
base.Dispose(disposing);
// We do not dispose the BaseStream because this stream
// is just a wrapper.
}
public override int EndRead(IAsyncResult asyncResult)
{
return GetBaseStream().EndRead(asyncResult);
}
public override void EndWrite(IAsyncResult asyncResult)
{
GetBaseStream().EndWrite(asyncResult);
}
public override bool Equals(object obj)
{
return GetBaseStream().Equals(obj);
}
public override void Flush()
{
GetBaseStream().Flush();
}
public override int GetHashCode()
{
return GetBaseStream().GetHashCode();
}
public override object InitializeLifetimeService()
{
return GetBaseStream().InitializeLifetimeService();
}
public override long Length
{
get { return GetBaseStream().Length; }
}
public override long Position
{
get { return GetBaseStream().Position; }
set { GetBaseStream().Position = value; }
}
public override int Read(byte[] buffer, int offset, int count)
{
return GetBaseStream().Read(buffer, offset, count);
}
public override int ReadByte()
{
return GetBaseStream().ReadByte();
}
public override int ReadTimeout
{
get { return GetBaseStream().ReadTimeout; }
set { GetBaseStream().ReadTimeout = value; }
}
public override long Seek(long offset, SeekOrigin origin)
{
return GetBaseStream().Seek(offset, origin);
}
public override void SetLength(long value)
{
GetBaseStream().SetLength(value);
}
public override string ToString()
{
return GetBaseStream().ToString();
}
public override void Write(byte[] buffer, int offset, int count)
{
GetBaseStream().Write(buffer, offset, count);
}
public override void WriteByte(byte value)
{
GetBaseStream().WriteByte(value);
}
public override int WriteTimeout
{
get { return GetBaseStream().WriteTimeout; }
set { GetBaseStream().WriteTimeout = value; }
}
}
此类旨在用作和输出到的流之间的XmlWriter
流。XmlWriter
此类只是将所有调用从 转发XmlWriter
到基本流,但是一旦您调用DisconnectBaseStream
,它就会停止转发它们并且XmlWriter
无法再控制基本流。
你可以像这样使用这个类:
using (var stream = /* stream used to communicate with */)
{
using (var wrapperStream = new DummyStream(stream))
using (var writer = XmlWriter.Create(wrapperStream))
{
// Do you work here.
// Now, disconnect the dummy stream so that the XML writer
// cannot send more data.
wrapperStream.DisconnectBaseStream();
// End of the using block will close the XmlWriter and it
// cannot send more data to the base stream.
}
// Perform TLS negotiation etc...
}
同样,这DummyStream
是一个起点,需要一些工作。例如,您将希望确保XmlWriter
在断开连接后不会进行调用,这将导致崩溃,因此您将需要检查Write
方法是否BaseStream
是null
,如果是,则跳过调用。