c# - C# での読み書き

Question

ファイル（画像）と別のファイルのビデオをC＃で読み取り、両方のファイルのすべての内容を（1つずつ）単一のtxtファイルに保存（書き込み）したい.今、最初の画像ファイルの内容と2番目のファイルを再度取得したい内容は別途。単一のファイルに保存するためにビデオと画像ファイルを読み取ることは可能ですか?

Answer 1

もちろん...

2 つの入力ストリームinfile1とinfile21 つの出力ストリームがあるとしますoutfile1。ファイル形式を次のように指定します。{Infile 1 Length in 8 bytes},{Infile 2 Length in 8 bytes},{Infile 1 data},{Infile 2 data}

public static void Main(string[] args)
{
    using (Stream infile1 = File.Open("Foobar.jpg", FileMode.Open, FileAccess.Read, FileShare.Read))
    using (Stream infile2 = File.Open("Foobar.avi", FileMode.Open, FileAccess.Read, FileShare.Read))
    using (Stream outfile = File.Open("Out.bin", FileMode.Create, FileAccess.Write, FileShare.None))
    {
        // write lengths
        byte[] file1Len = BitConverter.GetBytes(infile1.Length);
        byte[] file2Len = BitConverter.GetBytes(infile2.Length);

        outfile.Write(file1Len, 0, 8);
        outfile.Write(file2Len, 0, 8);

        // write data
        infile1.CopyTo(outfile);
        infile2.CopyTo(outfile);
    }

    // read file 1
    using (Stream combinedFile = File.Open("out.bin", FileMode.Open, FileAccess.Read, FileShare.Read))
    {
        byte[] file1len = new byte[8];
        combinedFile.Read(file1len, 0, 8);
        long lFile1Len = BitConverter.ToInt64(file1len, 0);

        // advance past header
        combinedFile.Position = 16;

        // limit
        var limStream = new LimitedStream(combinedFile, lFile1Len);

        // use the file as normal
        var bmp = System.Drawing.Bitmap.FromStream(limStream);
        bmp.Save(@"C:\drop\demo.jpg");
    }

    // read file 2
    using (Stream combinedFile = File.Open("out.bin", FileMode.Open, FileAccess.Read, FileShare.Read))
    {
        byte[] file1len = new byte[8];
        combinedFile.Read(file1len, 0, 8);
        long lFile1Len = BitConverter.ToInt64(file1len, 0);

        byte[] file2len = new byte[8];
        combinedFile.Read(file2len, 0, 8);
        long lFile2Len = BitConverter.ToInt64(file2len, 0);

        // advance past header and first file
        combinedFile.Position = 16 + lFile1Len;

        // limit
        var limStream = new LimitedStream(combinedFile, lFile2Len);

        // copy video out
        var tempPath = System.IO.Path.GetTempFileName();
        using (Stream outStr = File.Open(tempPath, FileMode.Create, FileAccess.Write, FileShare.None))
        {
            limStream.CopyTo(outStr);
        }
    }
}

public class LimitedStream : Stream
{
    long StartPosition = 0;
    long FunctionalLength = 0;
    long EndPosition { get { return StartPosition + FunctionalLength; } }
    Stream BaseStream = null;

    public LimitedStream(Stream baseStream, long length)
    {
        StartPosition = baseStream.Position;
        FunctionalLength = length;
        BaseStream = baseStream;
    }

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

    public override bool CanSeek
    {
        get { return BaseStream.CanSeek; }
    }

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

    public override void Flush()
    {
        BaseStream.Flush();
    }

    public override long Length
    {
        get { return FunctionalLength; }
    }

    public override long Position
    {
        get
        {
            return BaseStream.Position - StartPosition;
        }
        set
        {
            BaseStream.Position = value + StartPosition;
        }
    }

    public override int Read(byte[] buffer, int offset, int count)
    {
        if (BaseStream.Position + count > EndPosition)
            count = (int)(EndPosition - BaseStream.Position);
        // if there is no more data, return no read
        if (count < 1)
            return 0;

        return BaseStream.Read(buffer, offset, count);
    }

    public override long Seek(long offset, SeekOrigin origin)
    {
        if (origin == SeekOrigin.Current)
            return BaseStream.Seek(offset, origin);
        else if (origin == SeekOrigin.Begin)
            return BaseStream.Seek(offset - StartPosition, origin);
        else if (origin == SeekOrigin.End)
            return BaseStream.Seek(BaseStream.Length - EndPosition + offset, origin);
        else throw new NotSupportedException();
    }

    public override void SetLength(long value)
    {
        throw new NotSupportedException();
    }

    public override void Write(byte[] buffer, int offset, int count)
    {
        throw new NotSupportedException();
    }
}