c# - 如何在 .NET 中将 StreamWriter 的源设置为多个？

Question

我正在用 .NET 开发一些网络程序。我想在我的输出窗口上看到整个文本流作为日志。所以我试图搜索在 StreamWriter 上设置多个源的解决方案。但我找不到。我想要像下面这样的样式而不是扩展方法:

var sw = new StreamWriter(socketStream, traceStream)

或

var sw = new StreamWriter(socketStream);
sw.setSecondStream(traceStream);

Answer 1

制作分流器应该不难。对于没有 Seek 函数的只写流，它非常简单。

构造函数调用看起来像

var sw = new StreamWriter(new WriteStreamSplitter(socketStream, traceStream));

和类(class)(未经测试，只是一个模型)

class WriteStreamSplitter : Stream
{
    public WriteStreamSplitter(Stream a, Stream b)
    {
        _streamA = a;
        _streamB = b;
    }

    public override void Write(byte[] buffer, int offset, int count)
    {
        _streamA.Write(buffer, offset, count);
        _streamB.Write(buffer, offset, count);
    }

    public override bool CanWrite { get { return true; } }
    public override bool CanRead  { get { return false; } }

    // trivial overloads of all other abstract members, 
    // they are allowed to throw NotImplemented


    protected override void Dispose(bool disposing)
    {
        base.Dispose(disposing);
        if (disposing)
        {
            // Maybe it's best to do nothing here but a StreamWriter 
            // assumes 'ownership' of the wrapped stream, 
            // so if we want to continue that pattern:

            // the guidelines say these shouldn't throw
            _streamA.Dispose();
            _streamB.Dispose();
        }
    }
}