Copying from a network share

Hi Guys,

I'm looking for a way to copy files on a network share to a local folder. I'm now doing this via a mapped network connection, but as this sometimes times out I would like to do this in the software.

I've come across this piece of code:

Imports System.Runtime.InteropServices
Imports System.Net
Imports System.ComponentModel

Public Class NetworkConnection
    Implements IDisposable

    Private _networkName As String

    Public Sub New(networkName As String, credentials As NetworkCredential)
        _networkName = networkName

        Dim ntResource = New NetResource() With { _
            .Scope = ResourceScope.GlobalNetwork, _
            .ResourceType = ResourceType.Disk, _
            .DisplayType = ResourceDisplaytype.Share, _
            .RemoteName = networkName _

        Dim userName = If(String.IsNullOrEmpty(credentials.Domain), credentials.UserName, String.Format("{0}\{1}", credentials.Domain, credentials.UserName))

        Dim result = WNetAddConnection2(ntResource, credentials.Password, userName, 0)

        If result <> 0 Then
            Throw New Win32Exception(result, "Error connecting to remote share")
        End If
    End Sub

    Public Sub Dispose() Implements IDisposable.Dispose
    End Sub

    Protected Overrides Sub Finalize()
        End Try
    End Sub

    Protected Overridable Sub Dispose(disposing As Boolean)
        WNetCancelConnection2(_networkName, 0, True)
    End Sub

    <DllImport("mpr.dll")> _
    Private Shared Function WNetAddConnection2(netResource As NetResource, password As String, username As String, flags As Integer) As Integer
    End Function

    <DllImport("mpr.dll")> _
    Private Shared Function WNetCancelConnection2(name As String, flags As Integer, force As Boolean) As Integer
    End Function
End Class

<StructLayout(LayoutKind.Sequential)> _
Public Class NetResource
    Public Scope As ResourceScope
    Public ResourceType As ResourceType
    Public DisplayType As ResourceDisplaytype
    Public Usage As Integer
    Public LocalName As String
    Public RemoteName As String
    Public Comment As String
    Public Provider As String
End Class

Public Enum ResourceScope As Integer
    Connected = 1
End Enum

Public Enum ResourceType As Integer
    Any = 0
    Disk = 1
    Print = 2
    Reserved = 8
End Enum

Public Enum ResourceDisplaytype As Integer
    Generic = &H0
    Domain = &H1
    Server = &H2
    Share = &H3
    File = &H4
    Group = &H5
    Network = &H6
    Root = &H7
    Shareadmin = &H8
    Directory = &H9
    Tree = &HA
    Ndscontainer = &HB
End Enum

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Which is then used by a call like this (simplified):

        Dim cred As Net.NetworkCredential
        cred = New Net.NetworkCredential(*User*, *Pass)

            Using (New NetworkConnection(String.Format("\\{0}", *NetworkIP*), cred))
                IO.File.Copy(*RemoteFile*, *LocalFile*, true)
            End Using
        Catch ex as exception
            *Error handling*
        End try

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This solution works great.... as long as now File Explorer windows are opened. As soon as an Explorer window is opened, authentication fails (even if the Explorer window hasn't even touched the remote PC).

Question: Is there a better way to do this (preferably) or is there a way to close all Explorer windows (without killing off the main Explorer.exe process)

Who is Participating?
Shaun VermaakConnect With a Mentor Technical Specialist/DeveloperCommented:
I would impersonate and use File.Copy
Imports System.IO
Imports System.Security.Principal

Dim wid As WindowsIdentity = New WindowsIdentity("username", "password")
Dim context As WindowsImpersonationContext = wid.Impersonate()

File.Copy("\\\Share$\test.txt", "C:\Temp\test.txt", True)


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mvdrielAuthor Commented:
Your solution didn't work out of the box (it gave me an "invalid username" error), but pointed me in the right direction. Impersonating is the way to go. Thanks!
Shaun VermaakTechnical Specialist/DeveloperCommented:
Glad we could help.

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