Пример использования функций для работы с разреженными потоками

static void ExampleSparse()
{
    //Create new file. Delete the file before restart example!
    FileStream FS = new FileStream(@"d:\file.fil", FileMode.CreateNew);
    for (int i = 0; i < 1000; i++)
        for (byte b = 0; b < 250; b++)
            FS.WriteByte(b);
    FS.Flush();

    //Size of not compressed file
    Console.WriteLine("File Size: {0}", FS.Length);
    Console.WriteLine("Occupied: {0}", FS.GetLengthCompressed());

    //Print first 16 bytes
    Console.WriteLine();
    PrintFirst16Bytes(FS);

    //Zero first 8 bytes in not sparse file
    FS.SetZeroData(new Range(0, 8));
    PrintFirst16Bytes(FS);

    //Make file sparse
    FS.SetSparseAtribute(true);

    //Zero first 0-64k and 128k-196k
    FS.SetZeroData(new Range(0, 64 * 1024));
    FS.SetZeroData(new Range(128 * 1024, 64 * 1024));
    Console.WriteLine();
    Console.WriteLine("Occupied after two 64k-blocks zeroed: {0}", FS.GetLengthCompressed());
    PrintOccupiedRegions(FS);

    //Write one byte in removed region
    FS.Position = 1000;
    FS.WriteByte(0);
    FS.Flush(); 
    Console.WriteLine();
    Console.WriteLine("Occupied after 1 byte written (may be wrong): {0}", FS.GetLengthCompressed());
    System.Threading.Thread.Sleep(1000);
    Console.WriteLine("After pause: {0}", FS.GetLengthCompressed());            
    PrintOccupiedRegions(FS);

    //Print occupied Regions
    Console.WriteLine();
    Console.WriteLine("Refill file");
    FS.RefillZeroRegions();
    PrintOccupiedRegions(FS);


    FS.SetSparseAtribute(false);
    FS.Close();
}

static void PrintFirst16Bytes(FileStream FS)
{
    StringBuilder SB = new StringBuilder();
    FS.Position = 0;
    for (int i = 0; i < 16; i++)
        SB.AppendFormat(" {0:x2}", FS.ReadByte());
    Console.WriteLine("First 16 bytes: {0}", SB.ToString());
}

static void PrintOccupiedRegions(FileStream FS)
{
    Console.WriteLine("Occupied regions:");
    foreach (var R in FS.GetAllocatedRanges())
        Console.WriteLine(" {0} , {1}", R.Start, R.Length);
}