Loading Bitmap pictures from external DLL on VB 6.0

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Introduction

With this sample, you can use Bitmap stored on external file (DLL). Then you can use bitmaps from Windows system or you create your bitmap repository inside VB DLL. It's useful to create bitmap library without keep a lot of files on hard disk. On that case, anyone can erase the pictures.

Module Code

Type GUID
     Data1 As Long
     Data2 As Integer
     Data3 As Integer
     Data4(7) As Byte
End Type

Type PicBmp
     Size As Long
     Type As Long
     hBmp As Long
     hPal As Long
     Reserved As Long
End Type

Declare Function OleCreatePictureIndirect Lib "olepro32.dll" _
           (PicDesc As PicBmp, RefIID As GUID, ByVal fPictureOwnHandle As Long, _
           IPic As IPicture) As Long
Declare Function LoadBitmap Lib "user32" Alias "LoadBitmapA" _
               (ByVal hInstance As Long, ByVal lpBitmapID As Long) As Long
Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long
Declare Function LoadLibrary Lib "kernel32" Alias "LoadLibraryA" _
               (ByVal lpLibFileName As String) As Long
Declare Function FreeLibrary Lib "kernel32" _
               (ByVal hLibModule As Long) As Long

'Exemplo em SHELL32.DLL com ID 131               
Public Function LoadPictureDLL(sResourceFileName As String, _
                        ByVal lResourceId As Long) As Picture
     Dim hInst As Long
     Dim hBmp  As Long
     Dim Pic As PicBmp
     
     Dim IPic As IPicture
     Dim IID_IDispatch As GUID
     Dim lRC As Long
     
     
     hInst = LoadLibrary(sResourceFileName)
     If hInst <> 0 Then
          hBmp = LoadBitmap(hInst, lResourceId)
          If hBmp <> 0 Then
               IID_IDispatch.Data1 = &H20400
               IID_IDispatch.Data4(0) = &HC0
               IID_IDispatch.Data4(7) = &H46
               Pic.Size = Len(Pic)
               Pic.Type = vbPicTypeBitmap
               Pic.hBmp = hBmp
               Pic.hPal = 0
               lRC = OleCreatePictureIndirect(Pic, IID_IDispatch, 1, IPic)
               If lRC = 0 Then
                    Set LoadPictureDLL = IPic
                    Set IPic = Nothing
               Else
                    Call DeleteObject(hBmp)
               End If
          End If
          FreeLibrary (hInst)
          hInst = 0
     End If
End Function

Sample

The sample application has a better code sample. Download it to get more information.