/// <summary>
/// 压缩数据流。
/// </summary>
/// <param name="algorithm">要使用的压缩算法。CompressionAlgorithms 类中提供了常用的压缩算法。</param>
/// <param name="inputStream">指定输入流。</param>
/// <param name="inputCount">输入流的长度，或 -1 以代表读至流的末尾。</param>
/// <param name="outputStream">指定输出流。</param>
/// <returns></returns>
/// <exception cref="System.ArgumentNullException"></exception>
public static void Compression(CompressionAlgorithm algorithm, CompressionMode mode, Stream inputStream, int inputCount, Stream outputStream)
{
if (algorithm == null || inputStream == null || outputStream == null) throw new ArgumentNullException();
if (inputCount == 0)
return;
var countRead = 0;
var lastTimeRead = 0;
var inputBuffer = new byte[Compressor.ChunkSize];
do {
lastTimeRead = inputStream.Read(inputBuffer, 0, inputCount == -1 ? Compressor.ChunkSize : Math.Min(Compressor.ChunkSize, (inputCount - countRead)));
if (lastTimeRead != 0) {
countRead += lastTimeRead;
if (mode == CompressionMode.Compress) {
var ret = algorithm.CompressFinalBlock(inputBuffer, 0, lastTimeRead);
outputStream.Write(ret, 0, ret.Length);
}
else {
var ret = algorithm.DecompressFinalBlock(inputBuffer, 0, lastTimeRead);
outputStream.Write(ret, 0, ret.Length);
}
}
}
while ((countRead < inputCount && inputCount != -1) || (inputCount == -1 && lastTimeRead != 0));
}
/// <summary>
/// 压缩数据流。
/// </summary>
/// <param name="algorithm">要使用的压缩算法。CompressionAlgorithms 类中提供了常用的压缩算法。</param>
/// <param name="inputBuffer">指定输入缓冲区。</param>
/// <returns></returns>
/// <exception cref="System.ArgumentNullException"></exception>
public static byte[] Compression(CompressionAlgorithm algorithm, CompressionMode mode, byte[] inputBuffer)
{
if (algorithm == null || inputBuffer == null) throw new ArgumentNullException();
if (mode == CompressionMode.Compress)
return algorithm.CompressFinalBlock(inputBuffer, 0, inputBuffer.Length);
else
return algorithm.DecompressFinalBlock(inputBuffer, 0, inputBuffer.Length);
}
