使用GZipStream对MemoryStream进行编程压缩/解压缩

Question

我构建(基于CodeProject文章)一个包装类(C#)来使用a GZipStream来压缩a MemoryStream.它压缩很好但不会减压.我看了很多其他有相同问题的例子,我觉得我跟着说的是什么,但是当我解压缩时仍然没什么.这是压缩和解压缩方法:

public static byte[] Compress(byte[] bSource)
{

    using (MemoryStream ms = new MemoryStream())
    {
        using (GZipStream gzip = new GZipStream(ms, CompressionMode.Compress, true))
        {
            gzip.Write(bSource, 0, bSource.Length);
            gzip.Close();
        }

        return ms.ToArray();
    }
}


public static byte[] Decompress(byte[] bSource)
{

    try
    {
        using (MemoryStream ms = new MemoryStream())
        {
            using (GZipStream gzip = new GZipStream(ms, CompressionMode.Decompress, true))
            {
                gzip.Read(bSource, 0, bSource.Length);
                gzip.Close();
            }

            return ms.ToArray();
        }
    }
    catch (Exception ex)
    {
        throw new Exception("Error decompressing byte array", ex);
    }
}

这是我如何使用它的一个例子:

string sCompressed = Convert.ToBase64String(CompressionHelper.Compress("Some Text"));
// Other Processes
byte[] bReturned = CompressionHelper.Decompress(Convert.FromBase64String(sCompressed));
// bReturned has no elements after this line is executed

Answer 1

解压缩方法中存在一个错误.

代码不读取内容bSource.相反,它覆盖了从基于空内存流创建的空gzip读取的内容.

基本上你的代码版本在做什么:

//create empty memory
using (MemoryStream ms = new MemoryStream())

//create gzip stream over empty memory stream
using (GZipStream gzip = new GZipStream(ms, CompressionMode.Compress, true))

// write from empty stream to bSource
gzip.Write(bSource, 0, bSource.Length);

修复程序可能如下所示:

public static byte[] Decompress(byte[] bSource)
{
    using (var inStream = new MemoryStream(bSource))
    using (var gzip = new GZipStream(inStream, CompressionMode.Decompress))
    using (var outStream = new MemoryStream())
    {
        gzip.CopyTo(outStream);
        return outStream.ToArray();
    }
}