When using an
in .NET, it is often useful to be able to ascertain if the file selected resides on a network drive. If this is the case and you will be storing the file path for others to use (in a database for example), then you are relying on all users having the same drives mapped to the same letters.
The following code will convert a file path to a UNC path if the file is on a network drive.
'Function will take a file path and if it points to a
'mapped drive then it will return the UNC path.
Public Shared Function convertFilePath(ByVal strPath As String) As String
'First check if file path is already a UNC path.
If strPath.Length > 2 Then
If strPath.Substring(0, 2) = "\\" Then Return strPath 'If it is return it.
'Path is too short so return strPath to stop app from crashing
'Path is not already a UNC path so use a
'Windows Script Host Object Model to search all
'network drives and record their letters and
'paths in a hashtable.
Dim htCurrentMappings As New Hashtable
Dim objQuery As New WqlObjectQuery("select DriveType,DeviceID,ProviderName from Win32_LogicalDisk where DriveType=4")
Dim objScope As New ManagementScope("\\.\root\CIMV2")
objScope.Options.Impersonation = ImpersonationLevel.Impersonate
objScope.Options.EnablePrivileges = True
Dim objSearcher As New ManagementObjectSearcher(objScope, objQuery)
For Each objManagementObject As ManagementObject In objSearcher.Get
'Mapped drive letters and paths are now stored
'Get drive letter from strPath
Dim strDriveLetter As String = strPath.Substring(0, 2)
'Check if drive letter is a network drive
If htCurrentMappings.Contains(strDriveLetter) Then
'If it is return path with drive letter replaced by UNC path
Return strPath.Replace(strDriveLetter, htCurrentMappings(strDriveLetter).ToString)
'Else just return path as it is most likely local
To use the function with an
, use the following code:
Dim strCorrectedPath as String
Dim objFileBrowser As New OpenFileDialog
If objFileBrowser.ShowDialog() = Windows.Forms.DialogResult.OK Then
You will need a reference to the Windows Script Host Object Model COM component for this code to work.