如何使用一臺StreamWriter寫入多個基礎流？

Question

我正在寫文本到System.IO.StreamWriter。

基礎流（在new StreamWriter(underlyingStream)中指定）寫入遠程文件。 （我不認爲它的類型是相關的，但爲了完整起見，我會提到它是一個微軟azure CloudBlobStream underlyingStream）。

現在，我想通過在StreamWriter和第二個CloudBlobStream之間使用GZipOutputStream compressedUnderlyingStream來編寫一個具有相同內容的附加壓縮文件來擴展此功能。

我正在尋找一種方法來指定CloudBlobStream s作爲StreamWriter的基礎流。但我找不到方法。是否存在可組合兩個基礎流的流類型？或者我該如何解決這個問題？注意我希望一切都保持爲流，以最大限度地減少內存中的數據量。

//disregard lack of using statements for this example's sake 
CloudBlobStream blobStream = blob.OpenWrite(); 
CloudBlobStream compressedBlobStream = compressedBlob.OpenWrite(); 
GZipOutputStream compressorStream = new GZipOutputStream(compressedBlobStream); 
//I make the streamwriter here for the regular blob, 
///but how could I make the same streamwriter also write to the compressedBlob at the same time? 
TextWriter streamWriter = new StreamWriter(blobStream, Encoding.UTF8); 

Answer 1

我不認爲一個人把我的頭頂部，但它是微不足道的編寫自己：

class MultiStream : Stream 
{ 
    private List<Stream> streams; 

    public Streams(IEnumerable<Stream> streams) 
    { 
     this.streams = new List<Stream>(streams); 
    } 

    ... 

    public override void Write(byte[] buffer, int offset, int count) 
    { 
     foreach(Stream stream in streams) 
      stream.Write(buffer, offset, count); 
    } 

    ... 
}