使用 SharpZipLib 进行压缩的辅助类，简化压缩字节数组和字符串的操作

using System; using System.Text; using System.IO; using ICSharpCode.SharpZipLib.BZip2; using ICSharpCode.SharpZipLib.GZip; using ICSharpCode.SharpZipLib.Zip; namespace Compression { /**//// <summary> /// 压缩方式。 /// </summary> public enum CompressionType { /**//// <summary> /// GZip 压缩格式 /// </summary> GZip, /**//// <summary> /// BZip2 压缩格式 /// </summary> BZip2, /**//// <summary> /// Zip 压缩格式 /// </summary> Zip } /**//// <summary> /// 使用 SharpZipLib 进行压缩的辅助类，简化对字节数组和字符串进行压缩的操作。 /// </summary> public class CompressionHelper { /**//// <summary> /// 压缩供应者，默认为 GZip。 /// </summary> public static CompressionType CompressionProvider = CompressionType.GZip; Public methods#region Public methods /**//// <summary> /// 从原始字节数组生成已压缩的字节数组。 /// </summary> /// <param name="bytesToCompress">原始字节数组。</param> /// <returns>返回已压缩的字节数组</returns> public static byte[] Compress(byte[] bytesToCompress) { MemoryStream ms = new MemoryStream(); Stream s = OutputStream(ms); s.Write(bytesToCompress, 0, bytesToCompress.Length); s.Close(); return ms.ToArray(); } /**//// <summary> /// 从原始字符串生成已压缩的字符串。 /// </summary> /// <param name="stringToCompress">原始字符串。</param> /// <returns>返回已压缩的字符串。</returns> public static string Compress(string stringToCompress) { byte[] compressedData = CompressToByte(stringToCompress); string strOut = Convert.ToBase64String(compressedData); return strOut; } /**//// <summary> /// 从原始字符串生成已压缩的字节数组。 /// </summary> /// <param name="stringToCompress">原始字符串。</param> /// <returns>返回已压缩的字节数组。</returns> public static byte[] CompressToByte(string stringToCompress) { byte[] bytData = Encoding.Unicode.GetBytes(stringToCompress); return Compress(bytData); } /**//// <summary> /// 从已压缩的字符串生成原始字符串。 /// </summary> /// <param name="stringToDecompress">已压缩的字符串。</param> /// <returns>返回原始字符串。</returns> public string DeCompress(string stringToDecompress) { string outString = string.Empty; if (stringToDecompress == null) { throw new ArgumentNullException("stringToDecompress", "You tried to use an empty string"); } try { byte[] inArr = Convert.FromBase64String(stringToDecompress.Trim()); outString = Encoding.Unicode.GetString(DeCompress(inArr)); } catch (NullReferenceException nEx) { return nEx.Message; } return outString; } /**//// <summary> /// 从已压缩的字节数组生成原始字节数组。 /// </summary> /// <param name="bytesToDecompress">已压缩的字节数组。</param> /// <returns>返回原始字节数组。</returns> public static byte[] DeCompress(byte[] bytesToDecompress) { byte[] writeData = new byte[4096]; Stream s2 = InputStream(new MemoryStream(bytesToDecompress)); MemoryStream outStream = new MemoryStream(); while (true) { int size = s2.Read(writeData, 0, writeData.Length); if (size > 0) { outStream.Write(writeData, 0, size); } else { break; } } s2.Close(); byte[] outArr = outStream.ToArray(); outStream.Close(); return outArr; } #endregion Private methods#region Private methods /**//// <summary> /// 从给定的流生成压缩输出流。 /// </summary> /// <param name="inputStream">原始流。</param> /// <returns>返回压缩输出流。</returns> private static Stream OutputStream(Stream inputStream) { switch (CompressionProvider) { case CompressionType.BZip2: return new BZip2OutputStream(inputStream); case CompressionType.GZip: return new GZipOutputStream(inputStream); case CompressionType.Zip: return new ZipOutputStream(inputStream); default: return new GZipOutputStream(inputStream); } } /**//// <summary> /// 从给定的流生成压缩输入流。 /// </summary> /// <param name="inputStream">原始流。</param> /// <returns>返回压缩输入流。</returns> private static Stream InputStream(Stream inputStream) { switch (CompressionProvider) { case CompressionType.BZip2: return new BZip2InputStream(inputStream); case CompressionType.GZip: return new GZipInputStream(inputStream); case CompressionType.Zip: return new ZipInputStream(inputStream); default: return new GZipInputStream(inputStream); } } #endregion } }