需要ICSharpCode.SharpZipLib.dll，网上下载的到。
代码是从网上找来的：
1 public class ZipClass 2 { 3 #region 加压 4 /// 5 /// 功能：压缩文件（暂时只压缩文件夹下一级目录中的文件，文件夹及其子级被忽略） 6 /// 7 /// 被压缩的文件夹夹路径 8 /// 生成压缩文件的路径，为空则默认与被压缩文件夹同一级目录，名称为：文件夹名 +.zip 9 /// 出错信息 10 /// 是否压缩成功 11 static public bool ZipFile( string dirPath, string zipFilePath, out string err) 12 { 13 err = ""; 14 if (dirPath == string .Empty) 15 { 16 err = "要压缩的文件夹不能为空！ "; 17 return false ; 18 } 19 if (!Directory .Exists(dirPath)) 20 { 21 err = "要压缩的文件夹不存在！ "; 22 return false ; 23 } 24 //压缩文件名为空时使用文件夹名＋ zip 25 if (zipFilePath == string .Empty) 26 { 27 if (dirPath.EndsWith("\\" )) 28 { 29 dirPath = dirPath.Substring(0, dirPath.Length - 1); 30 } 31 zipFilePath = dirPath + ".zip"; 32 } 33 34 try 35 { 36 string[] filenames = Directory .GetFiles(dirPath); 37 using (ZipOutputStream s = new ZipOutputStream(File .Create(zipFilePath))) 38 { 39 s.SetLevel(9); 40 byte[] buffer = new byte[4096]; 41 foreach (string file in filenames) 42 { 43 ZipEntry entry = new ZipEntry( Path.GetFileName(file)); 44 entry.DateTime = DateTime.Now; 45 s.PutNextEntry(entry); 46 using (FileStream fs = File.OpenRead(file)) 47 { 48 int sourceBytes; 49 do 50 { 51 sourceBytes = fs.Read(buffer, 0, buffer.Length); 52 s.Write(buffer, 0, sourceBytes); 53 } while (sourceBytes > 0); 54 } 55 } 56 s.Finish(); 57 s.Close(); 58 } 59 } 60 catch (Exception ex) 61 { 62 err = ex.Message; 63 return false ; 64 } 65 return true ; 66 } 67 68 #endregion 69 70 #region 解压方法 71 /// 72 /// 功能：解压 zip格式的文件。 73 /// 74 /// 压缩文件路径 75 /// 解压文件存放路径 ,为空时默认与压缩文件同一级目录下，跟压缩文件同名的文件夹 76 /// 出错信息 77 /// 解压是否成功 78 static public bool UnZipFile( string zipFilePath, string unZipDir, out string err) 79 { 80 err = ""; 81 if (zipFilePath == string .Empty) 82 { 83 err = "压缩文件不能为空！"; 84 return false ; 85 } 86 if (!File .Exists(zipFilePath)) 87 { 88 err = "压缩文件不存在！"; 89 return false ; 90 } 91 //解压文件夹为空时默认与压缩文件同一级目录下，跟压缩文件同名的文件夹 92 if (unZipDir == string .Empty) 93 unZipDir = zipFilePath.Replace( Path.GetFileName(zipFilePath), Path.GetFileNameWithoutExtension(zipFilePath)); 94 if (!unZipDir.EndsWith("\\" )) 95 unZipDir += "\\"; 96 if (!Directory .Exists(unZipDir)) 97 Directory.CreateDirectory(unZipDir); 98 99 try100 {101 using (ZipInputStream s = new ZipInputStream(File .OpenRead(zipFilePath)))102 {103 104 ZipEntry theEntry;105 while ((theEntry = s.GetNextEntry()) != null)106 {107 string directoryName = Path .GetDirectoryName(theEntry.Name);108 string fileName = Path .GetFileName(theEntry.Name);109 if (directoryName.Length > 0)110 {111 Directory.CreateDirectory(unZipDir + directoryName);112 }113 if (!directoryName.EndsWith("\\"))114 directoryName += "\\";115 if (fileName != String .Empty)116 {117 using (FileStream streamWriter = File.Create(unZipDir + theEntry.Name))118 {119 120 int size = 2048;121 byte[] data = new byte[2048];122 while (true )123 {124 size = s.Read(data, 0, data.Length);125 if (size > 0)126 {127 streamWriter.Write(data, 0, size);128 }129 else130 {131 break;132 }133 }134 }135 }136 } //while137 }138 }139 catch (Exception ex)140 {141 err = ex.Message;142 return false ;143 }144 return true ;145 } //解压结束146 #endregion147 }