因为工作需要写了一个文件传输的东东
使用了System.Runtime.Remoting
客户端接口类：
Namespace Nail.Net.Remoting.Trans
Public Interface iTransFile
Function SendFile(ByVal FileName As String, ByVal bytes() As Byte, ByVal ClientCrc As Integer) As Integer
Function CompareFile(ByVal FileName As String, ByVal ClientCrc As Integer) As Boolean
Function GetFileDet(ByVal FileName As String) As Integer
Function GetFileInfo(ByVal FileName As String) As Byte()
Function GetFileInfo(ByVal FileName As String, ByVal Length As Integer) As Byte()
Function GetFileInfo(ByVal FileName As String, ByVal Point As Integer, ByVal Length As Integer) As Byte()
Property ServerTransSaveFilePath() As String
Property ServerTempFilePath() As String
End Interface
End Namespace
客户端类：（文件传输的实现在此）（包含1个窗体 后面窗体代码我会贴出来）（请添加引用System.Runtime.Remoting .net默认是不引用的 服务器端类同样）
Imports System.Runtime
Imports System.Runtime.Remoting
Imports System.Runtime.Remoting.Channels
Imports System.Runtime.Remoting.Channels.Tcp
Imports System.IO
Imports System.Threading
Namespace Nail.Net.Remoting.Client
Public Class FileTransClient
Private TransTempSize As Integer
Private TransType As TrType
Private TransPort As Integer
Private TransServerClassName As String
Private TransServerIpAdr As String
Private TransCRC32 As Integer
Private Tsc As Nail.Net.Remoting.Trans.iTransFile
Private Senconds As Integer = 10
Private WithEvents Timer1 As New System.Windows.Forms.Timer
Private NewTransForm As FrmTransfersUI
Private TransFileName As String
'文件全路径
Public Property FullFileName() As String
Get
Return TransFileName
End Get
Set(ByVal Value As String)
TransFileName = Value
End Set
End Property
'缓存属性
Public Property TempSize() As Integer
Get
Return TempSize
End Get
Set(ByVal Value As Integer)
Me.TransTempSize = Value
End Set
End Property
'端口属性
Public Property Port() As Integer
Get
Return Port
End Get
Set(ByVal Value As Integer)
Me.TransPort = Value
End Set
End Property
'服务器端服务名属性
Public Property ServerClassName() As String
Get
Return ServerClassName
End Get
Set(ByVal Value As String)
Me.TransServerClassName = Value
End Set
End Property
'服务器端IP地址属性
Public Property ServerIpAdr() As String
Get
Return ServerIpAdr()
End Get
Set(ByVal Value As String)
Me.TransServerIpAdr = Value
End Set
End Property
'枚举传输类型
Enum TrType
TCP = 1
HTTP = 2
End Enum
'传输类别属性
Public Property Type() As TrType
Get
Return TransType
End Get
Set(ByVal Value As TrType)
Me.TransType = Value
End Set
End Property
'连接服务器
Public Sub ConnetServer()
Try
Select Case TransType
Case TrType.TCP
Tsc = Activator.GetObject(GetType(Nail.Net.Remoting.Trans.iTransFile), "tcp://" & TransServerIpAdr & ":" & TransPort & "/" & TransServerClassName)
Case TrType.HTTP
Tsc = Activator.GetObject(GetType(Nail.Net.Remoting.Trans.iTransFile), "http://" & TransServerIpAdr & ":" & TransPort & "/" & TransServerClassName)
End Select
Catch ex As Exception
MsgBox(ex.ToString)
End Try
End Sub
Public Function CheckFileInfo(ByVal FileName As String) As Integer
Dim crc As New Nail.FileTools.clsCrc32
Return crc.CalcuateFile(FileName)
End Function
Public Sub SendFile()
ShowUI()
Timer1.Interval = 10
Timer1.Start()
Dim SendThead As New Thread(AddressOf SendFileToServer)
SendThead.Start()
End Sub
'发送文件方法
Private Sub SendFileToServer()
Dim Crc As Integer = CheckFileInfo(TransFileName)
Dim Fif As New FileInfo(TransFileName)
Dim FileSm As New FileStream(TransFileName, FileMode.Open, FileAccess.Read, FileShare.Read)
If FileSm.Length = 0 Then
MsgBox("这是个空文件 请选择一个有效文件！")
Exit Sub
End If
Dim bty(TransTempSize - 1) As Byte
Dim Star As Integer = 0
Dim i As Long
NewTransForm.MaxOfProgress = FileSm.Length '进度条总量
NewTransForm.FileSize = Fif.Length / 1000 & "Kbyte" '文件大小
NewTransForm.TransfersFileName = Fif.Name '文件名
Try
If (Fif.Length / TransTempSize).ToString.IndexOf(".") > 0 Then
If (Fif.Length / TransTempSize).ToString.Substring(0, 1) = "0" Then
ReDim bty(Fif.Length - 1)
FileSm.Read(bty, 0, bty.Length)
Tsc.SendFile(Fif.Name, bty, Crc)
With NewTransForm
.RateOfProgress = bty.Length '进度条当前值
.PercentOfProgress = "100%" '已完成的百分比
.LeaveTime = "完成" '剩余时间
.Transed = bty.Length & "byte" '已传输文件量
.RateOfTransfers = Math.Floor(bty.Length / Senconds) & "Kbyte/秒" '传输速度
End With
Else
For i = Math.Floor(Fif.Length / TransTempSize) To 1 Step -1
FileSm.Read(bty, 0, bty.Length)
Tsc.SendFile(Fif.Name, bty, Crc)
With NewTransForm
.RateOfProgress = Star
.PercentOfProgress = Math.Floor(NewTransForm.pgbTransfers.Value / NewTransForm.pgbTransfers.Maximum * 100) & "%"
If Star > 0 Then
.LeaveTime = TimeSpan.FromSeconds(Math.Floor((Fif.Length - Star) / 1000 / Math.Floor(Star / Senconds))).ToString
End If
.Transed = Star / 1000 & "Kbyte"
.RateOfTransfers = Math.Floor(Star / Senconds) & "Kbyte/秒"
End With
Star += TransTempSize
FileSm.Seek(Star, SeekOrigin.Begin)
Next
ReDim bty((Fif.Length - (Math.Floor(Fif.Length / TransTempSize)) * TransTempSize) - 1)
FileSm.Read(bty, 0, bty.Length)
Tsc.SendFile(Fif.Name, bty, Crc)
With NewTransForm
.RateOfProgress = .pgbTransfers.Maximum '进度条当前值
.PercentOfProgress = "100%"
.LeaveTime = "完成"
.Transed = FileSm.Length / 1000 & "Kbyte"
.RateOfTransfers = Math.Floor(Star / Senconds) & "Kbyte/秒" '传输速度
End With
End If
Else
For i = Math.Floor(Fif.Length / TransTempSize) To 1 Step -1
FileSm.Read(bty, 0, bty.Length)
Tsc.SendFile(Fif.Name, bty, Crc)
With NewTransForm
.RateOfProgress = Star
.PercentOfProgress = Math.Floor(NewTransForm.pgbTransfers.Value / NewTransForm.pgbTransfers.Maximum * 100) & "%"
.Transed = Star / 1000 & "Kbyte"
If Star > 0 Then
.LeaveTime = TimeSpan.FromSeconds(Math.Floor((Fif.Length - Star) / 1000 / Math.Floor(Star / Senconds))).ToString
End If
.RateOfTransfers = Math.Floor(Star / Senconds) & "Kbyte/秒" '传输速度
End With
Star += TransTempSize
FileSm.Seek(Star, SeekOrigin.Begin)
Next
NewTransForm.LeaveTime = "完成"
End If
NewTransForm.btnCancle.Text = "确 定"
Me.Timer1.Stop()
Senconds = 10
'NewTransForm.Close()
'MsgBox("传输完成")
Catch ex As Exception
MsgBox(ex.ToString)
End Try
FileSm.Close()
End Sub
'接受文件方法
Public Function GetFile(ByVal _filename As String) As Integer
End Function
'记时
Private Sub Timer1_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Senconds += 10
End Sub
Public Function ShowUI() As Integer
NewTransForm = New FrmTransfersUI
NewTransForm.Show()
Return 0
End Function
End Class
End Namespace
客户端窗体（显示文件传输的进度 时间 大小 。。。。。）
Public Class FrmTransfersUI
Inherits System.Windows.Forms.Form
#Region " Windows 窗体设计器生成的代码 "
Public Sub New()
MyBase.New()
'该调用是 Windows 窗体设计器所必需的。
InitializeComponent()
'在 InitializeComponent() 调用之后添加任何初始化
End Sub
'窗体重写 dispose 以清理组件列表。
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
'Windows 窗体设计器所必需的
Private components As System.ComponentModel.IContainer
'注意: 以下过程是 Windows 窗体设计器所必需的
'可以使用 Windows 窗体设计器修改此过程。
'不要使用代码编辑器修改它。
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents pgbTransfers As System.Windows.Forms.ProgressBar
Friend WithEvents Button2 As System.Windows.Forms.Button
Friend WithEvents lblRateOfTransfers As System.Windows.Forms.Label
Friend WithEvents lblTransfersFileName As System.Windows.Forms.Label
Friend WithEvents btnCancle As System.Windows.Forms.Button
Friend WithEvents lblFileSize As System.Windows.Forms.Label
Friend WithEvents lblLeaveTime As System.Windows.Forms.Label
Friend WithEvents lblPercentOfProgress As System.Windows.Forms.Label
Friend WithEvents lblTransed As System.Windows.Forms.Label
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.Button1 = New System.Windows.Forms.Button
Me.pgbTransfers = New System.Windows.Forms.ProgressBar
Me.Button2 = New System.Windows.Forms.Button
Me.lblRateOfTransfers = New System.Windows.Forms.Label
Me.lblTransed = New System.Windows.Forms.Label
Me.lblTransfersFileName = New System.Windows.Forms.Label
Me.btnCancle = New System.Windows.Forms.Button
Me.lblFileSize = New System.Windows.Forms.Label
Me.lblLeaveTime = New System.Windows.Forms.Label
Me.lblPercentOfProgress = New System.Windows.Forms.Label
Me.SuspendLayout()
'
'Button1
'
Me.Button1.Dock = System.Windows.Forms.DockStyle.Fill
Me.Button1.Enabled = False
Me.Button1.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.Button1.Location = New System.Drawing.Point(0, 0)
Me.Button1.Name = "Button1"
Me.Button1.Size = New System.Drawing.Size(448, 136)
Me.Button1.TabIndex = 0
'
'pgbTransfers
'
Me.pgbTransfers.Location = New System.Drawing.Point(10, 16)
Me.pgbTransfers.Name = "pgbTransfers"
Me.pgbTransfers.Size = New System.Drawing.Size(430, 12)
Me.pgbTransfers.TabIndex = 1
'
'Button2
'
Me.Button2.Enabled = False
Me.Button2.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.Button2.Location = New System.Drawing.Point(4, 4)
Me.Button2.Name = "Button2"
Me.Button2.Size = New System.Drawing.Size(442, 130)
Me.Button2.TabIndex = 2
'
'lblRateOfTransfers
'
Me.lblRateOfTransfers.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.lblRateOfTransfers.Location = New System.Drawing.Point(10, 36)
Me.lblRateOfTransfers.Name = "lblRateOfTransfers"
Me.lblRateOfTransfers.Size = New System.Drawing.Size(220, 14)
Me.lblRateOfTransfers.TabIndex = 3
Me.lblRateOfTransfers.Text = "传输速度:"
'
'lblTransed
'
Me.lblTransed.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.lblTransed.Location = New System.Drawing.Point(10, 58)
Me.lblTransed.Name = "lblTransed"
Me.lblTransed.Size = New System.Drawing.Size(220, 14)
Me.lblTransed.TabIndex = 4
Me.lblTransed.Text = "已 传 送:"
'
'lblTransfersFileName
'
Me.lblTransfersFileName.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.lblTransfersFileName.Location = New System.Drawing.Point(10, 80)
Me.lblTransfersFileName.Name = "lblTransfersFileName"
Me.lblTransfersFileName.Size = New System.Drawing.Size(220, 14)
Me.lblTransfersFileName.TabIndex = 5
Me.lblTransfersFileName.Text = "传输文件:"
'
'btnCancle
'
Me.btnCancle.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.btnCancle.Location = New System.Drawing.Point(192, 104)
Me.btnCancle.Name = "btnCancle"
Me.btnCancle.TabIndex = 6
Me.btnCancle.Text = "取 消"
'
'lblFileSize
'
Me.lblFileSize.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.lblFileSize.Location = New System.Drawing.Point(246, 80)
Me.lblFileSize.Name = "lblFileSize"
Me.lblFileSize.Size = New System.Drawing.Size(192, 14)
Me.lblFileSize.TabIndex = 9
Me.lblFileSize.Text = "文件大小:"
'
'lblLeaveTime
'
Me.lblLeaveTime.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.lblLeaveTime.Location = New System.Drawing.Point(246, 58)
Me.lblLeaveTime.Name = "lblLeaveTime"
Me.lblLeaveTime.Size = New System.Drawing.Size(192, 14)
Me.lblLeaveTime.TabIndex = 8
Me.lblLeaveTime.Text = "剩余时间:"
'
'lblPercentOfProgress
'
Me.lblPercentOfProgress.FlatStyle = System.Windows.Forms.FlatStyle.System
Me.lblPercentOfProgress.Location = New System.Drawing.Point(246, 36)
Me.lblPercentOfProgress.Name = "lblPercentOfProgress"
Me.lblPercentOfProgress.Size = New System.Drawing.Size(192, 14)
Me.lblPercentOfProgress.TabIndex = 7
Me.lblPercentOfProgress.Text = "传输进度:"
'
'FrmTransfersUI
'
Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
Me.ClientSize = New System.Drawing.Size(448, 136)
Me.Controls.Add(Me.lblFileSize)
Me.Controls.Add(Me.lblLeaveTime)
Me.Controls.Add(Me.lblPercentOfProgress)
Me.Controls.Add(Me.btnCancle)
Me.Controls.Add(Me.lblTransfersFileName)
Me.Controls.Add(Me.lblTransed)
Me.Controls.Add(Me.lblRateOfTransfers)
Me.Controls.Add(Me.pgbTransfers)
Me.Controls.Add(Me.Button2)
Me.Controls.Add(Me.Button1)
Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None
Me.Name = "FrmTransfersUI"
Me.ShowInTaskbar = False
Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen
Me.Text = "FrmTransfersUI"
Me.TopMost = True
Me.ResumeLayout(False)
End Sub
#End Region
Public Event UserCancle()
Public WriteOnly Property MaxOfProgress()
Set(ByVal Value)
Me.pgbTransfers.Maximum = Value
End Set
End Property
Public WriteOnly Property RateOfProgress()
Set(ByVal Value)
Me.pgbTransfers.Value = Value
End Set
End Property
Public WriteOnly Property RateOfTransfers() As String
Set(ByVal Value As String)
Me.lblRateOfTransfers.Text = "传输速度:" & Value
End Set
End Property
Public WriteOnly Property Transed() As String
Set(ByVal Value As String)
Me.lblTransed.Text = "已 传 送:" & Value
End Set
End Property
Public WriteOnly Property TransfersFileName() As String
Set(ByVal Value As String)
Me.lblTransfersFileName.Text = "传输文件:" & Value
End Set
End Property
Public WriteOnly Property PercentOfProgress() As String
Set(ByVal Value As String)
Me.lblPercentOfProgress.Text = "传输进度:" & Value
End Set
End Property
Public WriteOnly Property LeaveTime() As String
Set(ByVal Value As String)
Me.lblLeaveTime.Text = "剩余时间:" & Value
End Set
End Property
Public WriteOnly Property FileSize() As String
Set(ByVal Value As String)
Me.lblFileSize.Text = "文件大小:" & Value
End Set
End Property
Private Sub btnCancle_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCancle.Click
If Me.btnCancle.Text = "确 定" Then
Me.Close()
Else
RaiseEvent UserCancle()
End If
End Sub
End Class
服务器端类 下面还有个模块
Imports System.Runtime
Imports System.Runtime.Remoting
Imports System.Runtime.Remoting.Channels
Imports System.Runtime.Remoting.Channels.Tcp
Imports System.IO
Namespace Nail.Net.Remoting.Server
Public Class FileTransServer
Private TransServerClassName As String
Private TransType As TrType
Private TransPort As Integer
Private TransCRC32 As Integer
Enum TrType
TCP = 1
HTTP = 2
End Enum
Public Property Type() As TrType
Get
Return TransType
End Get
Set(ByVal Value As TrType)
Me.TransType = Value
End Set
End Property
Public Property ServerTransSaveFilePath() As String
Get
Return TransSaveFilePath
End Get
Set(ByVal Value As String)
TransSaveFilePath = Value
End Set
End Property
Public Property ServerTempFilePath() As String
Get
Return TempFilePath
End Get
Set(ByVal Value As String)
TempFilePath = Value
End Set
End Property
Public Property ServerClassName() As String
Get
Return ServerClassName
End Get
Set(ByVal Value As String)
Me.TransServerClassName = Value
End Set
End Property
Public Property Port() As Integer
Get
Return Port
End Get
Set(ByVal Value As Integer)
Me.TransPort = Value
End Set
End Property
Public Sub StarServer()
Select Case TransType
Case TrType.TCP
Dim a As New System.Runtime.Remoting.Channels.Tcp.TcpChannel(TransPort)
ChannelServices.RegisterChannel(a)
Case TrType.HTTP
Dim a As New System.Runtime.Remoting.Channels.Http.HttpChannel(TransPort)
ChannelServices.RegisterChannel(a)
End Select
System.Runtime.Remoting.RemotingConfiguration.ApplicationName = TransServerClassName
RemotingConfiguration.RegisterWellKnownServiceType(GetType(TransFile), TransServerClassName, WellKnownObjectMode.SingleCall)
End Sub
End Class
Public Class TransFile
Inherits MarshalByRefObject
Implements Nail.Net.Remoting.Trans.iTransFile
Public Function CompareFile(ByVal FileName As String, ByVal ClientCrc As Integer) As Boolean Implements Nail.Net.Remoting.Trans.iTransFile.CompareFile
Dim crc As New Nail.FileTools.clsCrc32
If crc.CalcuateFile(FileName) = ClientCrc Then
Return True
Else
Return False
End If
End Function
Public Function GetFileDet(ByVal FileName As String) As Integer Implements Nail.Net.Remoting.Trans.iTransFile.GetFileDet
Dim c As New FileInfo(FileName)
Return c.Length
End Function
Public Function GetFileInfo(ByVal FileName As String) As Byte() Implements Nail.Net.Remoting.Trans.iTransFile.GetFileInfo
Dim FullName As String = FileName
Dim c As New FileInfo(FullName)
Return GetFileInfo(FileName, 0, c.Length)
End Function
Public Function GetFileInfo(ByVal FileName As String, ByVal Length As Integer) As Byte() Implements Nail.Net.Remoting.Trans.iTransFile.GetFileInfo
Return GetFileInfo(FileName, 0, Length)
End Function
Public Function GetFileInfo(ByVal FileName As String, ByVal Point As Integer, ByVal Length As Integer) As Byte() Implements Nail.Net.Remoting.Trans.iTransFile.GetFileInfo
Dim FullName As String = FileName
Dim c As New FileInfo(FullName)
Dim x As New FileStream(FullName, FileMode.Open, FileAccess.Read, FileShare.Read)
Dim bty(Length - 1) As Byte
x.Seek(Point, SeekOrigin.Begin)
x.Read(bty, 0, Length)
Return bty
End Function
Public Function SendFile(ByVal FileName As String, ByVal bytes() As Byte, ByVal ClientCrc As Integer) As Integer Implements Nail.Net.Remoting.Trans.iTransFile.SendFile
Try
Dim a As New FileStream(TempFilePath & FileName, FileMode.OpenOrCreate)
a.Seek(a.Length, SeekOrigin.Begin)
a.Write(bytes, 0, bytes.Length)
a.Close()
Return 0
Catch ex As Exception
MsgBox(ex.ToString)
Return 1
Finally
'Dim Finf As New FileInfo(TempFilePath & FileName)
'If CompareFile(TempFilePath & FileName, ClientCrc) = True Then
' '拷贝临时文件()
' File.Copy(TempFilePath & FileName, TransSaveFilePath & FileName, True)
'Else
' '删除临时文件()
' Finf.Delete()
'End If
End Try
End Function
Public Property ServerTempFilePath() As String Implements Nail.Net.Remoting.Trans.iTransFile.ServerTempFilePath
Get
Return TempFilePath
End Get
Set(ByVal Value As String)
TempFilePath = Value
End Set
End Property
Public Property ServerTransSaveFilePath() As String Implements Nail.Net.Remoting.Trans.iTransFile.ServerTransSaveFilePath
Get
Return TransSaveFilePath
End Get
Set(ByVal Value As String)
TransSaveFilePath = Value
End Set
End Property
End Class
End Namespace
模块：
Module Server
Public TransSaveFilePath As String
Public TempFilePath As String
End Module
使用方法：
服务器端
示例：
Dim Server As New Nail.Net.Remoting.Server.FileTransServer
Server.ServerClassName = "aaa"
Server.Port = 10001
Server.Type = Nail.Net.Remoting.Server.FileTransServer.TrType.HTTP
Server.ServerTempFilePath = "f:\"
Server.ServerTransSaveFilePath = "e:\"
Server.StarServer()
客户端
cl.Port = 10001
cl.ServerClassName = "aaa"
cl.TempSize = 102400
cl.ServerIpAdr = "localhost"
cl.FullFileName = "c:\111.rar"
cl.Type = Nail.Net.Remoting.Client.FileTransClient.TrType.HTTP
cl.ConnetServer()
发送文件：
cl.SendFile()
最后忘记贴文件校对了 照书上搞的CRC32
Imports System.IO
Namespace Nail.FileTools
Public Class clsCrc32
Private Const TABLESIZE As Integer = 256
Private Const DEFAULTPOLYNOMIAL As Integer = &HEDB88320
Private Const DEFAULTIALVALUE As Integer = &HFFFFFFFF
Private lookup(TABLESIZE - 1) As Integer
Private crcPolynomial As Integer = 0
Public Sub New()
Me.New(DEFAULTPOLYNOMIAL)
End Sub
Public Sub New(ByVal crcPolynomial As Integer)
Me.crcPolynomial = crcPolynomial
InitLookupTable()
End Sub
Public Property Polynomial() As Integer
Get
Return crcPolynomial
End Get
Set(ByVal Value As Integer)
Me.crcPolynomial = Value
InitLookupTable()
End Set
End Property
Public Overloads Function CalculateBlock(ByVal bytes() As Byte) As Integer
Return CalculateBlock(bytes, 0, bytes.Length)
End Function
Public Overloads Function CalculateBlock(ByVal bytes() As Byte, ByVal index As Integer, ByVal length As Integer) As Integer
Return CalculateBlock(bytes, index, length, DEFAULTIALVALUE)
End Function
Public Overloads Function CalculateBlock(ByVal bytes() As Byte, ByVal index As Integer, ByVal length As Integer, ByVal initialValue As Integer) As Integer
If bytes Is Nothing Then
ElseIf index < 0 Or length <= 0 Or index + length > bytes.Length Then
End If
Return Not internalcalculateBlock(bytes, index, length, initialValue)
End Function
Private Function internalcalculateBlock(ByVal bytes() As Byte, ByVal index As Integer, ByVal length As Integer, ByVal initialValue As Integer) As Integer
Dim crc As Integer = initialValue
Dim shiftCrc As Integer
Dim position As Integer
For position = index To length - 1
shiftCrc = crc And &HFFFFFF00
shiftCrc = shiftCrc / &H100
shiftCrc = shiftCrc And &HFFFFFF
crc = shiftCrc Xor lookup(bytes(position)) Xor (crc And &HFF)
Next
Return crc
End Function
Public Overloads Function CalcuateFile(ByVal path As String) As Integer
Return CalcuateFile(path, DEFAULTIALVALUE)
End Function
Public Overloads Function CalcuateFile(ByVal path As String, ByVal initialValue As Integer) As Integer
If path Is Nothing Then
ElseIf path.Length = 0 Then
End If
Return Not InternalCalculateFile(path, initialValue)
End Function
Private Function InternalCalculateFile(ByVal path As String, ByVal initialValue As Integer) As Integer
Const blockSize As Integer = 4096
Dim count As Integer
Dim inStream As System.IO.FileStream
Dim bytes(blockSize - 1) As Byte
Dim crc As Integer = initialValue
Try
inStream = System.IO.File.Open(path, FileMode.Open, FileAccess.Read)
While inStream.Position < inStream.Length
count = inStream.Read(bytes, 0, blockSize)
crc = internalcalculateBlock(bytes, 0, count, crc)
End While
Finally
If Not inStream Is Nothing Then
inStream.Close()
End If
End Try
Return crc
End Function
Private Sub InitLookupTable()
Dim bytecount, bitcount As Integer
Dim crc, shiftCrc As Integer
For bytecount = 0 To TABLESIZE - 1
crc = bytecount
For bitcount = 0 To 7
shiftCrc = crc And &HFFFFFFFE
shiftCrc = shiftCrc \ &H2
shiftCrc = shiftCrc And &H7FFFFFFF
If (crc And &H1) Then
crc = shiftCrc Xor crcPolynomial
Else
crc = shiftCrc
End If
Next
lookup(bytecount) = crc
Next
End Sub
End Class
End Namespace
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