/// <summary>
/// Copy the contents of a stored file into an opened stream
/// </summary>
/// <param name="_zfe">Entry information of file to extract</param>
/// <param name="_stream">Stream to store the uncompressed data</param>
/// <returns>True if success, false if not.</returns>
/// <remarks>Unique compression methods are Store and Deflate</remarks>
public bool ExtractFile(ZipFileEntry _zfe, Stream _stream)
{
if (!_stream.CanWrite)
throw new InvalidOperationException("Stream cannot be written");
// check signature
byte[] signature = new byte[4];
this.ZipFileStream.Seek(_zfe.HeaderOffset, SeekOrigin.Begin);
this.ZipFileStream.Read(signature, 0, 4);
if (BitConverter.ToUInt32(signature, 0) != 0x04034b50)
return false;
// Select input stream for inflating or just reading
Stream inStream;
if (_zfe.Method == Compression.Store)
inStream = this.ZipFileStream;
else if (_zfe.Method == Compression.Deflate)
inStream = new DeflateStream(this.ZipFileStream, CompressionMode.Decompress, true);
else
return false;
// Buffered copy
byte[] buffer = new byte[16384];
this.ZipFileStream.Seek(_zfe.FileOffset, SeekOrigin.Begin);
uint bytesPending = _zfe.FileSize;
while (bytesPending > 0)
{
int bytesRead = inStream.Read(buffer, 0, (int)Math.Min(bytesPending, buffer.Length));
_stream.Write(buffer, 0, bytesRead);
bytesPending -= (uint)bytesRead;
}
_stream.Flush();
if (_zfe.Method == Compression.Deflate)
inStream.Dispose();
return true;
}
