Question

我正在尝试实施7z SDK来一次压缩和解压缩多个文件。

我一次尝试一个文件，并且两种方法都起作用，现在我对compress方法进行了一些更改，以支持压缩多个文件。

public static void CompressFile(List<string> inFiles, string outFile)
{
        SevenZip.Compression.LZMA.Encoder coder = new SevenZip.Compression.LZMA.Encoder();

        FileStream output = new FileStream(outFile, FileMode.Create);

        // Write the encoder properties
        coder.WriteCoderProperties(output);

        int listSize = inFiles.Count;

        // get the size of my list to loop through all the items
        // Writing each file on the compressed file at a time

        for(int i = 0; i < listSize; i++)
        {
            FileStream input = new FileStream(inFiles[i], FileMode.Open);

            // Write the decompressed file size.
            output.Write(BitConverter.GetBytes(input.Length), 0, 8);

            // Encode the file.
            coder.Code(input, output, input.Length, -1, null);
        }
        output.Flush();
        output.Close();
    }

我得到了预期的压缩文件，但是我需要实现decompress方法来测试一切是否正常。

我一直想弄清楚如何实施我需要解压缩多个文件的更改：

public static void DecompressFile(string inFile, string outFile)
{
        //Original method used to decompress one file worked.

        SevenZip.Compression.LZMA.Decoder coder = new SevenZip.Compression.LZMA.Decoder();


            FileStream input = new FileStream(inFile, FileMode.Open);
            FileStream output = new FileStream(outFile, FileMode.Create);

            // Read the decoder properties
            byte[] properties = new byte[5];
            input.Read(properties, 0, 5);

            // Read in the decompress file size.
            byte[] fileLengthBytes = new byte[8];
            input.Read(fileLengthBytes, 0, 8);
            long fileLength = BitConverter.ToInt64(fileLengthBytes, 0);

            coder.SetDecoderProperties(properties);
            coder.Code(input, output, input.Length, fileLength, null);
            output.Flush();
            output.Close();

    }

我有一个想法（不知道是否好）使用循环结构压缩所有文件，但是我无法解压缩。哪种方法最适合解压缩应该包含多个文件的文件？

Answer 1

我用gzipstream做过类似的事情。但这全都与您要如何打包文件有关。

在这种情况下，这将是理想的选择。

string payload = Path.GetTempFileName();
using (FileStream temp_fs = new FileStream(payload, FileMode.OpenOrCreate))
{
    using (BinaryWriter output_s = new BinaryWriter(new FileStream("target.out", FileMode.OpenOrCreate)))
    {
        //Write a blank. must be a long!
        output_s.Write((long)0);
        foreach (string file in Files)
        {

            //Write the files name
            output_s.Write(file);
            long start = temp_fs.Position;

            //Write the starting point
            output_s.Write(start);

            //Compress the file to the payload
            using (GZipStream gzip = new GZipStream(temp_fs, CompressionMode.Compress, true))
            {
                using (FileStream fs = new FileStream(file, FileMode.Open))
                {
                    fs.CopyTo(gzip);
                }
            }

            //Write the length
            output_s.Write(temp_fs.Position - start);
        }

        //When all files are written
        //Get the size of our header
        long headersize = output_s.BaseStream.Length - 8;

        //Copy the temp file data to the end
        temp_fs.CopyTo(output_s.BaseStream);

        //Reset to the start of the stream
        output_s.BaseStream.Position = 0;

        //override our zero
        output_s.Write(headersize);
    }

}
File.Delete(payload);

当您读取文件时，将执行二进制读取操作，您将能够按名称抓取文件，然后文件名后面的很长一段时间将是其大小并开始。那么您可以将节头+ pos解压缩为长度。检索您的文件。

使用7z SDK解压缩多个文件

1 个答案: