96 lines
2.6 KiB
C#
96 lines
2.6 KiB
C#
|
using System;
|
|||
|
|
using System.IO;
|
|||
|
|
using System.Runtime.InteropServices.WindowsRuntime;
|
|||
|
|
using System.Threading.Tasks;
|
|||
|
|
using Windows.Storage.Streams;
|
|||
|
|
|
|||
|
|
namespace Plane.Communication
|
|||
|
|
{
|
|||
|
|
/// <summary>
|
|||
|
|
/// 所有以字节流形式进行通信的 <see cref="IConnection"/> 实现者的基类。
|
|||
|
|
/// </summary>
|
|||
|
|
public abstract class StreamConnection : ExceptionThrownEventSource, IConnection
|
|||
|
|
{
|
|||
|
|
protected bool _canFlush = true;
|
|||
|
|
protected IInputStream _inputStream;
|
|||
|
|
protected Stream _outputStream;
|
|||
|
|
private bool _reopening;
|
|||
|
|
|
|||
|
|
public bool IsOpen { get; protected set; }
|
|||
|
|
|
|||
|
|
public virtual void Close()
|
|||
|
|
{
|
|||
|
|
IsOpen = false;
|
|||
|
|
try
|
|||
|
|
{
|
|||
|
|
_inputStream?.Dispose();
|
|||
|
|
}
|
|||
|
|
catch { }
|
|||
|
|
try
|
|||
|
|
{
|
|||
|
|
_outputStream?.Dispose();
|
|||
|
|
}
|
|||
|
|
catch { }
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
public abstract Task OpenAsync();
|
|||
|
|
|
|||
|
|
public virtual async Task<int> ReadAsync(byte[] buffer, int offset, int count)
|
|||
|
|
{
|
|||
|
|
try
|
|||
|
|
{
|
|||
|
|
IBuffer buf = new Windows.Storage.Streams.Buffer((uint)count);
|
|||
|
|
buf = await _inputStream.ReadAsync(buf, (uint)count, InputStreamOptions.None);
|
|||
|
|
buf.CopyTo(0, buffer, offset, count);
|
|||
|
|
return count;
|
|||
|
|
}
|
|||
|
|
catch (Exception ex)
|
|||
|
|
{
|
|||
|
|
RaiseExceptionThrown(ex);
|
|||
|
|
await ReopenIfNeededAsync();
|
|||
|
|
return 0;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
public virtual async Task WriteAsync(byte[] buffer, int offset, int count)
|
|||
|
|
{
|
|||
|
|
try
|
|||
|
|
{
|
|||
|
|
await _outputStream.WriteAsync(buffer, offset, count).ConfigureAwait(false);
|
|||
|
|
if (_canFlush)
|
|||
|
|
{
|
|||
|
|
await _outputStream.FlushAsync().ConfigureAwait(false);
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
catch (NotImplementedException) // 不支持 Flush。
|
|||
|
|
{
|
|||
|
|
_canFlush = false;
|
|||
|
|
}
|
|||
|
|
catch (Exception ex)
|
|||
|
|
{
|
|||
|
|
RaiseExceptionThrown(ex);
|
|||
|
|
await ReopenIfNeededAsync();
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
private async Task ReopenIfNeededAsync()
|
|||
|
|
{
|
|||
|
|
if (!_reopening)
|
|||
|
|
{
|
|||
|
|
_reopening = true;
|
|||
|
|
Close();
|
|||
|
|
try
|
|||
|
|
{
|
|||
|
|
await OpenAsync();
|
|||
|
|
}
|
|||
|
|
catch (Exception ex)
|
|||
|
|
{
|
|||
|
|
RaiseExceptionThrown(ex);
|
|||
|
|
await Task.Delay(1000);
|
|||
|
|
}
|
|||
|
|
_reopening = false;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|