Friend Function GetFilesViaBrowse()

in vsintegration/src/FSharp.ProjectSystem.PropertyPages/Common/Utils.vb [633:721]
73 lines of code
15 McCabe index (conditional complexity)

        Friend Function GetFilesViaBrowse(ByVal ServiceProvider As System.IServiceProvider, ByVal ParentWindow As IntPtr, _
                ByVal InitialDirectory As String, ByVal DialogTitle As String, _
                ByVal Filter As String, ByVal FilterIndex As UInteger, ByVal MutiSelect As Boolean, _
                Optional ByVal DefaultFileName As String = Nothing, _
                Optional ByVal NeedThrowError As Boolean = False) As ArrayList

            Dim uishell As IVsUIShell = _
                CType(ServiceProvider.GetService(GetType(IVsUIShell)), IVsUIShell)

            Dim fileNames As New ArrayList()

            InitialDirectory = NormalizeInitialDirectory(InitialDirectory)
            If InitialDirectory = "" Then
                InitialDirectory = Nothing
            End If

            Filter = GetNativeFilter(Filter)

            Dim MaxPathName As Integer = Interop.win.MAX_PATH + 1
            If MutiSelect Then
                MaxPathName = (Interop.win.MAX_PATH + 1) * VSDPLMAXFILES
            End If

            Dim vsOpenFileName As VSOPENFILENAMEW()

            Dim defaultName(MaxPathName) As Char
            If DefaultFileName IsNot Nothing Then
                DefaultFileName.CopyTo(0, defaultName, 0, DefaultFileName.Length)
            End If

            Dim stringMemPtr As IntPtr = System.Runtime.InteropServices.Marshal.AllocHGlobal(MaxPathName * 2 + 2)
            System.Runtime.InteropServices.Marshal.Copy(defaultName, 0, stringMemPtr, defaultName.Length)

            Try
                vsOpenFileName = New VSOPENFILENAMEW(0) {}
                vsOpenFileName(0).lStructSize = CUInt(System.Runtime.InteropServices.Marshal.SizeOf(vsOpenFileName(0)))
                vsOpenFileName(0).hwndOwner = ParentWindow
                vsOpenFileName(0).pwzDlgTitle = DialogTitle
                vsOpenFileName(0).nMaxFileName = CUInt(MaxPathName)
                vsOpenFileName(0).pwzFileName = stringMemPtr
                vsOpenFileName(0).pwzInitialDir = InitialDirectory
                vsOpenFileName(0).pwzFilter = Filter
                vsOpenFileName(0).nFilterIndex = FilterIndex
                vsOpenFileName(0).nFileOffset = 0
                vsOpenFileName(0).nFileExtension = 0
                vsOpenFileName(0).dwHelpTopic = 0

                If MutiSelect Then
                    vsOpenFileName(0).dwFlags = &H200   
                Else
                    vsOpenFileName(0).dwFlags = 0
                End If

                Dim hr As Integer = uishell.GetOpenFileNameViaDlg(vsOpenFileName)
                If VSErrorHandler.Succeeded(hr) Then
                    Dim buffer(MaxPathName) As Char
                    System.Runtime.InteropServices.Marshal.Copy(stringMemPtr, buffer, 0, buffer.Length)
                    Dim path As String = Nothing
                    Dim i As Integer = 0
                    For j As Integer = 0 To buffer.Length - 1
                        If buffer(j) = Chr(0) Then
                            If i = j Then
                                Exit For
                            End If
                            If i = 0 Then
                                path = New String(buffer, 0, j)
                            Else
                                fileNames.Add(path & IO.Path.DirectorySeparatorChar & New String(buffer, i, j - i))
                            End If
                            i = j + 1
                        End If
                    Next

                    If fileNames.Count = 0 AndAlso path IsNot Nothing Then
                        fileNames.Add(path)
                    End If
                ElseIf NeedThrowError Then
                    If hr = Interop.win.OLE_E_PROMPTSAVECANCELLED Then
                        
                    Else
                        VSErrorHandler.ThrowOnFailure(hr)
                    End If
                End If
            Finally
                System.Runtime.InteropServices.Marshal.FreeHGlobal(stringMemPtr)
            End Try

            Return fileNames
        End Function