【.NET】利用SharpZipLib压缩与解压文件夹中的所有文件、内存中动态压缩解压数据、内存中压缩与解压文本
SharpZipLib是一个非常优秀的.NET环境下的ZIP文档压缩与解压组件，免费且开源。
本篇文章介绍一下如何使用该组件压缩一个文件夹中的所有文件到ZIP文档、解压一个ZIP文档到文件夹，以及如何利用SharpZipLib在内存中动态的加解压数据。
下载最新版的SharpZipLibhttp://www.icsharpcode.net/OpenSource/SharpZipLib/Download.aspx
Imports System.IO Imports System.Text Imports ICSharpCode Imports ICSharpCode.SharpZipLib Imports ICSharpCode.SharpZipLib.Zip Imports ICSharpCode.SharpZipLib.Zip.Compression Imports ICSharpCode.SharpZipLib.Core Public Class iZip ''' <summary> 加压数据 </summary> ''' <param name="data"> 数据 </param> ''' <param name="offset"> 起始偏移 </param> ''' <param name="length"> 长度 </param> ''' <param name="level"> 压缩级别 </param> Public Shared Function Compress( ByVal data As Byte (), Optional ByVal offset As Integer = 0 , Optional ByVal length As Integer = - 1 , Optional ByVal level As Integer = 9 ) As Byte () If data Is Nothing OrElse data.Length = 0 Then Return Nothing If offset < 0 Then offset = 0 If length < 0 Then length = data.Length If level < 0 Then level = 1 If level > 9 Then level = 9 Dim ms As New MemoryStream Dim def As New Deflater def.SetLevel(level) def.SetInput(data, offset, length) Dim output( & H400 - 1 ) As Byte Do Until def.IsFinished Dim count As Integer = def.Deflate(output) ms.Write(output, 0 , count) Loop Dim ret As Byte () = ms.ToArray ms.Close() Return ret End Function ''' <summary> 加压字符 </summary> ''' <param name="str"> 字符 </param> ''' <param name="enc"> 编码 </param> ''' <param name="level"> 压缩级别 </param> Public Shared Function CompressString( ByVal str As String , Optional ByVal enc As Encoding = Nothing , Optional ByVal level As Integer = 9 ) As Byte () If enc Is Nothing Then enc = Encoding.Default Dim data As Byte () = enc.GetBytes( str ) Return Compress(data, , , level) End Function ''' <summary> 解压数据 </summary> ''' <param name="data"> 数据 </param> Public Shared Function Decompress( ByVal data As Byte ()) As Byte () If data Is Nothing OrElse data.Length < 1 Then Return Nothing Dim ms As New MemoryStream Dim inf As New Inflater inf.SetInput(data) Dim buffer( & H400 - 1 ) As Byte Do Until inf.IsFinished Dim count As Integer = inf.Inflate(buffer) ms.Write(buffer, 0 , count) Loop Dim ret As Byte () = ms.ToArray ms.Close() Return ret End Function ''' <summary> 解压字符 </summary> ''' <param name="data"> 数据 </param> ''' <param name="enc"> 编码 </param> Public Shared Function DecompressString( ByVal data As Byte (), Optional ByVal enc As Encoding = Nothing ) As String If enc Is Nothing Then enc = Encoding.Default Dim bs As Byte () = Decompress(data) Return enc.GetString(bs) End Function ''' <summary> 快速加压 </summary> Public Shared Sub FastCreateZip( ByVal zipPath As String , ByVal folderPath As String , Optional ByVal fileFilter As String = "" , Optional ByVal password As String = Nothing ) Dim fz As New FastZip If password <> Nothing Then fz.Password = password fz.CreateZip(zipPath, folderPath, True , fileFilter) End Sub ''' <summary> 快速解压 </summary> Public Shared Sub FastExtractZip( ByVal zipPath As String , ByVal folderPath As String , Optional ByVal fileFilter As String = "" , Optional ByVal password As String = Nothing ) Dim fz As New FastZip If password <> Nothing Then fz.Password = password fz.ExtractZip(zipPath, folderPath, fileFilter) End Sub ''' <summary> 解压ZIP文件到目录 </summary> ''' <param name="zipPath"> ZIP文件路径 </param> ''' <param name="folderPath"> 目标文件夹 </param> ''' <param name="password"> 密码 </param> ''' <param name="overwrite"> 是否覆盖文件 </param> Public Shared Sub DecompressZip( ByVal zipPath As String , ByVal folderPath As String , Optional ByVal password As String = Nothing , Optional ByVal overwrite As Boolean = True ) ' 初始化文档、密码、目标文件夹路径 Dim z As New ZipInputStream(File.OpenRead(zipPath)) If password <> Nothing Then z.Password = password If folderPath = Nothing Then ' folderPath = HttpContext.Current.Server.MapPath("~/") folderPath = Application.StartupPath End If If Not folderPath.EndsWith( " \ " ) Then folderPath &= " \ " If Not Directory.Exists(folderPath) Then Directory.CreateDirectory(folderPath) Dim t As ZipEntry Dim fp As String ' 开始循环解压 Do t = z.GetNextEntry If t Is Nothing Then Exit Do fp = folderPath & t.Name ' 如果是文件夹则创建文件夹 If t.IsDirectory AndAlso Not Directory.Exists(fp) Then Directory.CreateDirectory(fp) ElseIf t.IsFile Then ' 如果是文件则解压文件 If ( Not File.Exists(fp)) OrElse (File.Exists(fp) And overwrite) Then Dim sw As FileStream = File.Create(fp) Dim size As Integer Dim data( 2048 ) As Byte Do ' 循环读取数据 size = z.Read(data, 0 , data.Length) If size = 0 Then Exit Do sw.Write(data, 0 , size) Loop sw.Close() File.SetLastWriteTime(fp, t.DateTime) ' 更新创建日期 End If End If Loop z.Close() End Sub ''' <summary> 压缩某个目录内全部文档到ZIP </summary> ''' <param name="zipPath"> ZIP路径 </param> ''' <param name="folderPath"> 目标目录 </param> ''' <param name="level"> 压缩级别 </param> ''' <param name="password"> 密码 </param> Public Shared Sub CompressFile( ByVal zipPath As String , ByVal folderPath As String , Optional ByVal level As Integer = 9 , Optional ByVal password As String = Nothing ) If Not Directory.Exists(folderPath) Then Return If folderPath.EndsWith( " \ " ) Then folderPath &= " \ " Dim z As New ZipOutputStream(File.Create(zipPath)) z.SetLevel(level) If password <> Nothing Then z.Password = password Dim fn As String , buffer( 4096 ) As Byte Dim di As Integer = folderPath.Length + 1 ' 先将主目录下所有文件加入文档 For Each f As String In Directory.GetFiles(folderPath, " * " , SearchOption.TopDirectoryOnly) fn = f.Remove( 0 , di) z.PutNextEntry( New ZipEntry(fn)) ' 将文件数据写入ZIP Using fs As FileStream = File.OpenRead(f) StreamUtils.Copy(fs, z, buffer) End Using Next ' 枚举所有文件夹 For Each d As String In Directory.GetDirectories(folderPath, " * " , SearchOption.AllDirectories) fn = d.Remove( 0 , di) & " \ " z.PutNextEntry( New ZipEntry(fn)) ' 枚举所有文件 For Each f As String In Directory.GetFiles(d, " * " , SearchOption.TopDirectoryOnly) fn = f.Remove( 0 , di) z.PutNextEntry( New ZipEntry(fn)) Using fs As FileStream = File.OpenRead(f) StreamUtils.Copy(fs, z, buffer) End Using Next Next z.Close() End Sub End Class
其中数据动态加解压的代码分析来自Lucene.NET，其他的是参考网络上部分文章（来源不可考）。
我稍微封装了一下SharpZipLib的方法，可以更实用更方便一些。
实际上SharpZipLib有一个FastZip类，也很方便，但效率就稍微比自己写的方法低了一点。
代码未严格测试，有BUG或建议请指正。