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Imports System
Imports System.Collections.Generic
Imports System.IO
Imports System.Threading
' 此类别代表一个封存档。您可以将文件压缩后置入其中、将其所内含的压缩档解压缩出来、亦或是移除它所内含的压缩档。
Public Class ZipFile
Private zipEntries As List(Of ZipEntry)
Private thisReader As ZipReader
Private thisWriter As ZipWriter
Private baseStream As Stream
Private zipName As String
' 使用指定的名称建立一个新的压缩文件。
' 建构函式拥有两个多载版本。
' 此多载版本的建构函式拥有三个参数，分别是压缩文件的文件名称、压缩的方式、以及文件存取模式。
Public Sub New(ByVal name As String, ByVal method As Byte, ByVal mode As FileMode)
Try
zipName = name
baseStream = New FileStream(zipName, mode)
thisWriter = New ZipWriter(baseStream)
thisWriter.Method = method
' 新文件。
thisWriter.WriteSuperHeader(0, method)
Dim index1 As Integer = zipName.IndexOf(ZipConstants.Dot)
Dim index2 As Integer = zipName.LastIndexOf(ZipConstants.BackSlash)
thisReader = New ZipReader(baseStream, zipName.Substring(index2, index1 - index2))
zipEntries = thisReader.GetAllEntries()
CH2_DemoForm002.statusMessage = String.Format(Thread.CurrentThread.CurrentUICulture, ZipConstants.NewMessage, name)
Catch ex As IOException
ZipConstants.ShowError(ZipConstants.IOError)
End Try
End Sub 'New
' 此多载版本的构造函数会根据所提供的名称来打开一个压缩文件。
Public Sub New(ByVal name As String)
Try
zipName = name
baseStream = New FileStream(zipName, FileMode.Open)
thisWriter = New ZipWriter(baseStream)
Dim index1 As Integer = zipName.IndexOf(ZipConstants.Dot)
Dim index2 As Integer = zipName.LastIndexOf(ZipConstants.BackSlash)
thisReader = New ZipReader(baseStream, zipName.Substring(index2, index1 - index2))
zipEntries = thisReader.GetAllEntries()
thisWriter.Method = thisReader.Method
If CH2_DemoForm002.statusMessage = Nothing Or CH2_DemoForm002.statusMessage <> String.Empty Then
CH2_DemoForm002.statusMessage = String.Format(Thread.CurrentThread.CurrentUICulture, ZipConstants.OpenMessage, name)
End If
Catch ex As IOException
ZipConstants.ShowError("乐博网提示：打开文件发生错误")
Catch ex As ArgumentOutOfRangeException
ZipConstants.ShowError(ZipConstants.CorruptedError)
End Try
End Sub 'New
' 藉由加总所有个别项目的长度来决定所要跳跃的位移。
' 返回值：自 SeekOrigin.Begin 算起的位移。
Private Function GetOffset(ByVal index As Integer) As Long
If index > zipEntries.Count Then
Return -1
End If
Dim jump As Integer = ZipConstants.SuperHeaderSize
Dim i As Integer
i = 0
While i < index - 1
Dim entry As ZipEntry = zipEntries(i)
jump += ZipConstants.FixedHeaderSize + entry.NameLength + entry.CompressedSize
i += 1
End While
Return jump
End Function 'GetOffset
Public Sub Add(ByVal fileName As String)
Dim ci As System.Globalization.CultureInfo = Thread.CurrentThread.CurrentUICulture
If fileName.ToLower(ci).Equals(zipName.ToLower(ci)) Then
ZipConstants.ShowError("乐博网提示：无法新增至目前的 xip 文件")
CH2_DemoForm002.statusMessage = String.Empty
Return
End If
Dim entry As New ZipEntry(fileName)
thisWriter.Add(entry)
If CH2_DemoForm002.statusMessage.Length <> 0 Then
zipEntries.Add(entry)
thisWriter.CloseHeaders(CType(zipEntries.Count, Int16))
End If
End Sub 'Add '更多.net源码和教程，来自[乐博网 www.lob.cn]
Public Sub Extract(ByVal index As Integer, ByVal path As String)
If index < 0 OrElse index >= zipEntries.Count Then
ZipConstants.ShowError("自变量超出范围" + "异常")
Return
End If
thisReader.Extract(zipEntries(index), GetOffset((index + 1)), path)
End Sub 'Extract
Public Sub ExtractAll(ByVal path As String)
thisReader.ExtractAll(zipEntries, path)
End Sub 'ExtractAll
' 关闭压缩文档。它亦会关闭此类的所有输入数据流。
' 在此方法被调用之后，将不能调用其任何方法。
Public Sub Close()
If baseStream IsNot Nothing Then
baseStream.Close()
End If
End Sub 'Close
' 取得代表压缩文件的输入项目。
' 返回值： ZipEntries 的集合。
Public ReadOnly Property Entries() As List(Of ZipEntry)
Get
Return zipEntries
End Get
End Property
Public Function CompressionMethod() As Byte
Return thisWriter.Method
End Function
Public Function CheckFileExists(ByVal fileName As String) As Integer
Dim ci As System.Globalization.CultureInfo = Thread.CurrentThread.CurrentUICulture
Dim i As Integer = -1
Dim eachEntry As ZipEntry
For Each eachEntry In zipEntries
i += 1
If eachEntry.Name.ToLower(ci).Equals(fileName.ToLower(ci)) Then
Return i
End If
Next eachEntry
Return -1
End Function 'CheckFileExists
Private Sub DeleteEntryFromFile(ByVal index As Integer)
Dim jump As Long = ZipConstants.SuperHeaderSize
Dim i As Integer
While i < index
jump += ZipConstants.FixedHeaderSize + zipEntries(i).NameLength + zipEntries(i).CompressedSize
i += 1
End While
Dim entry As ZipEntry = zipEntries(index)
Dim fileJump As Long = ZipConstants.FixedHeaderSize + entry.NameLength + entry.CompressedSize
baseStream.Seek(jump + fileJump, SeekOrigin.Begin)
Dim length As Long = baseStream.Length - fileJump - jump
Dim b(length) As Byte
baseStream.Read(b, 0, CType(length, Integer))
baseStream.Seek(jump, SeekOrigin.Begin)
baseStream.Write(b, 0, CType(length, Integer))
baseStream.SetLength(baseStream.Length - fileJump)
CH2_DemoForm002.statusMessage = "乐博网提示：成功移除"
End Sub 'DeleteEntryFromFile
Public Sub Remove(ByVal index As Integer)
Dim jump As Long = ZipConstants.SuperHeaderSize
Dim i As Integer
While i < index
jump += ZipConstants.FixedHeaderSize + zipEntries(i).NameLength + zipEntries(i).CompressedSize
i += 1
End While
thisWriter.Remove(jump, zipEntries(index))
zipEntries.RemoveAt(index)
If CH2_DemoForm002.statusMessage.Length <> 0 Then
thisWriter.CloseHeaders(CType(zipEntries.Count, Int16))
End If
End Sub 'Remove
End Class 'ZipFile
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