.NET [VB.NET] Drag & Drop - Move files from desktop to a textbox

Code
Public Class Form1



    Private Structure FileFormat

        Public TypeFormat As String

    End Structure



    Private ff As New FileFormat



    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _

            Handles MyBase.Load

        With Me

            .CenterToScreen()

            .TextBox1.AllowDrop = True

            .ff.TypeFormat = "FileNameW"

        End With

    End Sub



    Private Function DragAndDrop_MoveLink(ByVal Filename As String) As String

        Const Filetype As String = ".lnk"

        If String.Compare(GetExtension(Filename), Filetype, True) <> 0 Then Return Filename

        Dim shell As Shell32.Shell = New Shell32.Shell

        Dim DirectoryName As Shell32.Folder = shell.NameSpace(GetDirectoryName(Filename))

        Dim Item As Shell32.FolderItem = DirectoryName.Items().Item(GetFileName(Filename))

        Dim LinkObject As Shell32.ShellLinkObject = CType(Item.GetLink, Shell32.ShellLinkObject)

        Return LinkObject.Path

    End Function



    Private Sub TextBox1_DragDrop(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) _

            Handles TextBox1.DragDrop

        If ff.TypeFormat = Nothing Then

            Throw New Exception("Error...")

        Else

            If e.Data.GetDataPresent(ff.TypeFormat, False) Then

                Dim Filename As System.Array = CType(e.Data.GetData(ff.TypeFormat, False), System.Array)

                TextBox1.Text = DragAndDrop_MoveLink(CType(Filename.GetValue(0), String))

            End If

        End If

    End Sub



    Private Sub TextBox1_DragOver(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) _

            Handles TextBox1.DragOver

        If ff.TypeFormat = Nothing Then

            Throw New Exception("Error...")

        Else

            If e.Data.GetDataPresent(ff.TypeFormat, False) Then

                e.Effect = DragDropEffects.Copy

            Else

                e.Effect = DragDropEffects.None

            End If

        End If

    End Sub



End Class