Распаковка Zip архива

using System.IO; 
using System.IO.Compression;

public void ungzip(string path, string decomPath, bool overwrite)
{
//for overwriting purposes
   if (File.Exists(decomPath))
   {
      if (overwrite)
      {
         File.Delete(decomPath);
      }
      else
      {
         throw new IOException("The decompressed path you specified already exists and cannot be overwritten.");
      }
   }
   //create our file streams
   GZipStream stream = new GZipStream(new FileStream(path, FileMode.Open, FileAccess.ReadWrite), CompressionMode.Decompress);
   FileStream decompressedFile = new FileStream(decomPath, FileMode.OpenOrCreate, FileAccess.Write);
   //data represents a byte from the compressed file
   //it's set through each iteration of the while loop
   int data;
   while ((data = stream.ReadByte()) != -1) //iterates over the data of the compressed file and writes the decompressed data
   {
      decompressedFile.WriteByte((byte)data);
   }
   //close our file streams 
   decompressedFile.Close();
   stream.Close();
}

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