在.net endsup中使用解压缩的零数组进行压缩和解压力

Question

我正在尝试压缩和解压缩内存流，以便通过tcp连接发送它。在下面的代码片段中，我确实在压缩之后立即进行了解压缩，以便首先让它工作。无论我做什么，我都会得到一个全为零的devompressed缓冲区，并且在int read = Decompress.Read(buffie，0，buffie.Length)行中；似乎读取了0个字节。

有没有人知道出了什么问题？

bytesRead = ms.Read(buf, 0, i);

MemoryStream partialMs = new MemoryStream();
GZipStream gZip = new GZipStream(partialMs, CompressionMode.Compress);

gZip.Write(buf, 0, buf.Length);

partialMs.Position = 0;

byte[] compressedBuf = new byte[partialMs.Length];

partialMs.Read(compressedBuf, 0, (int)partialMs.Length);

partialMs.Close();

byte[] gzBuffer = new byte[compressedBuf.Length + 4];
System.Buffer.BlockCopy(compressedBuf, 0, gzBuffer, 4, compressedBuf.Length);
System.Buffer.BlockCopy(BitConverter.GetBytes(buf.Length), 0, gzBuffer, 0, 4);

using (MemoryStream mems = new MemoryStream())
{
    int msgLength = BitConverter.ToInt32(gzBuffer, 0);

    byte[] buffie = new byte[msgLength];
    mems.Write(gzBuffer, 4, gzBuffer.Length - 4);
    mems.Flush();
    mems.Position = 0;

    using (GZipStream Decompress = new GZipStream(mems, CompressionMode.Decompress, true))
    {
        int read = Decompress.Read(buffie, 0, buffie.Length);
        Decompress.Close();
    }
}

Answer 1

您的实现可能需要一些工作。对于应该在哪里使用哪些流，似乎存在一些混乱。下面是一个可以帮助您入门的工作示例。

查看此MSDN page底部的用户内容

var original = new byte[65535];
var compressed = GZipTest.Compress(original);
var decompressed = GZipTest.Decompress(compressed);

using System.IO;
using System.IO.Compression;

public class GZipTest
{
    public static byte[] Compress(byte[] uncompressedBuffer)
    {
        using (var ms = new MemoryStream())
        {
            using (var gzip = new GZipStream(ms, CompressionMode.Compress, true))
            {
                gzip.Write(uncompressedBuffer, 0, uncompressedBuffer.Length);
            }
            byte[] compressedBuffer = ms.ToArray();
            return compressedBuffer;
        }
    }

    public static byte[] Decompress(byte[] compressedBuffer)
    {
        using (var gzip = new GZipStream(new MemoryStream(compressedBuffer), CompressionMode.Decompress))
        {
            byte[] uncompressedBuffer = ReadAllBytes(gzip);
            return uncompressedBuffer;
        }
    }

    private static byte[] ReadAllBytes(Stream stream)
    {
        var buffer = new byte[4096];
        using (var ms = new MemoryStream())
        {
            int bytesRead = 0;
            do
            {
                bytesRead = stream.Read(buffer, 0, buffer.Length);
                if (bytesRead > 0)
                {
                    ms.Write(buffer, 0, bytesRead);
                }
            } while (bytesRead > 0);

            return ms.ToArray();
        }
    }
}

Answer 2

您没有关闭您正在写入的GzipStream，所以它可能都是缓冲的。我建议你在写完数据后关闭它。

顺便说一句，使用MemoryStream.ToArray可以比使用当前代码更容易地从MemoryStream中获取数据。