image - excel vba 形式 image1.picture 控件中的 LoadImage PNG，黑色背景

Question

我有将 png 图像加载到图片控件的代码

Option Explicit
Option Private Module

Private Type GUID
    Data1 As Long
    Data2 As Integer
    Data3 As Integer
    Data4(0 To 7) As Byte
End Type

Private Type PICTDESC
    Size As Long
    Type As Long
    hPic As Long
    hPal As Long
End Type

Private Type GdiplusStartupInput
    GdiplusVersion As Long
    DebugEventCallback As Long
    SuppressBackgroundThread As Long
    SuppressExternalCodecs As Long
End Type

Private Declare Function GdiplusStartup Lib "GDIPlus" ( _
    token As Long, _
    inputbuf As GdiplusStartupInput, _
    Optional ByVal outputbuf As Long = 0) As Long

Private Declare Function GdipCreateBitmapFromFile Lib "GDIPlus" ( _
    ByVal FileName As Long, _
    bitmap As Long) As Long

Private Declare Function GdipCreateHBITMAPFromBitmap Lib "GDIPlus" ( _
    ByVal bitmap As Long, _
    hbmReturn As Long, _
    ByVal background As Long) As Long

Private Declare Function GdipDisposeImage Lib "GDIPlus" ( _
    ByVal Image As Long) As Long

Private Declare Function GdiplusShutdown Lib "GDIPlus" ( _
    ByVal token As Long) As Long

Private Declare Function OleCreatePictureIndirect Lib "olepro32.dll" ( _
    PicDesc As PICTDESC, _
    RefIID As GUID, _
    ByVal fPictureOwnsHandle As Long, _
    IPic As IPicture) As Long

Public Function LoadImage(ByVal strFName As String) As IPicture
    Dim uGdiInput As GdiplusStartupInput
    Dim hGdiPlus As Long
    Dim hGdiImage As Long
    Dim hBitmap As Long

    uGdiInput.GdiplusVersion = 1

    If GdiplusStartup(hGdiPlus, uGdiInput) = 0 Then
        If GdipCreateBitmapFromFile(StrPtr(strFName), hGdiImage) = 0 Then
            GdipCreateHBITMAPFromBitmap hGdiImage, hBitmap, 0
            Set LoadImage = ConvertToIPicture(hBitmap)
            GdipDisposeImage hGdiImage
        End If
            GdiplusShutdown hGdiPlus
    End If
End Function

Public Function ConvertToIPicture(ByVal hPic As Long) As IPicture
    Dim uPicInfo As PICTDESC
    Dim IID_IDispatch As GUID
    Dim IPic As IPicture

    Const PICTYPE_BITMAP = 1

    With IID_IDispatch
        .Data1 = &H7BF80980
        .Data2 = &HBF32
        .Data3 = &H101A
        .Data4(0) = &H8B
        .Data4(1) = &HBB
        .Data4(2) = &H0
        .Data4(3) = &HAA
        .Data4(4) = &H0
        .Data4(5) = &H30
        .Data4(6) = &HC
        .Data4(7) = &HAB
    End With

    With uPicInfo
        .Size = Len(uPicInfo)
        .Type = PICTYPE_BITMAP
        .hPic = hPic
        .hPal = 0
    End With

    OleCreatePictureIndirect uPicInfo, IID_IDispatch, True, IPic

    Set ConvertToIPicture = IPic
End Function

但是 png 图像加载时使用黑色背景而不是透明背景？如何解决这个问题？

Answer 1

我使用这个函数(注意该函数可以位于单独的模块中):

Private Sub UserForm_Activate()
With Me.Image1
    .BorderStyle = fmBorderStyleNone
    .PictureSizeMode = fmPictureSizeModeZoom
    .BackStyle = fmBackStyleTransparent
    .Picture = LoadImage("C:\images\MinersBag.png")
End With
end sub


Public Function LoadImagePat(ByVal h$) As IPicture 'si LoadImage ne marche pas , ou ne fait pas la transparance correct :
'code by lepelletier Patrick 28/02/2016

Dim Aff As Boolean
Dim Pic As Shape
With Application
    Aff = .ScreenUpdating
    .ScreenUpdating = False
End With
Set Pic = ActiveSheet.Pictures.Insert(h).ShapeRange(1)
With Pic
    .Copy
    Set LoadImagePat = PastePicture
    .Delete
End With
Set Pic = Nothing
If Aff Then Application.ScreenUpdating = True
End Function

PastPicture 例程由 Stephen Bullen 编写，可在 here 找到。 (direct download link)。为了防止链接失效，这里有一个 modPastePicture 的副本。将其全部保存到 modPastePicture.bas 中，然后将该文件导入到 VBA 编辑器中。

Attribute VB_Name = "modPastePicture"
'***************************************************************************
'*
'* MODULE NAME:     Paste Picture
'* AUTHOR & DATE:   STEPHEN BULLEN, Office Automation Ltd
'*                  15 November 1998
'*
'* CONTACT:         Stephen@oaltd.co.uk
'* WEB SITE:        http://www.oaltd.co.uk
'*
'* DESCRIPTION:     Creates a standard Picture object from whatever is on the clipboard.
'*                  This object can then be assigned to (for example) and Image control
'*                  on a userform.  The PastePicture function takes an optional argument of
'*                  the picture type - xlBitmap or xlPicture.
'*
'*                  The code requires a reference to the "OLE Automation" type library
'*
'*                  he code in this module has been derived from a number of sources
'*                  discovered on MSDN.
'*
'*                  To use it, just copy this module into your project, then you can use:
'*                      Set Image1.Picture = PastePicture(xlPicture)
'*                  to paste a picture of whatever is on the clipboard into a standard image control.
'*
'* PROCEDURES:
'*   PastePicture   The entry point for the routine
'*   CreatePicture  Private function to convert a bitmap or metafile handle to an OLE reference
'*   fnOLEError     Get the error text for an OLE error code
'***************************************************************************

Option Explicit
Option Compare Text

''' User-Defined Types for API Calls

'Declare a UDT to store a GUID for the IPicture OLE Interface
Private Type GUID
    Data1 As Long
    Data2 As Integer
    Data3 As Integer
    Data4(0 To 7) As Byte
End Type

'Declare a UDT to store the bitmap information
Private Type uPicDesc
    Size As Long
    Type As Long
    hPic As Long
    hPal As Long
End Type

'''Windows API Function Declarations

'Does the clipboard contain a bitmap/metafile?
Private Declare Function IsClipboardFormatAvailable Lib "user32" (ByVal wFormat As Integer) As Long

'Open the clipboard to read
Private Declare Function OpenClipboard Lib "user32" (ByVal hwnd As Long) As Long

'Get a pointer to the bitmap/metafile
Private Declare Function GetClipboardData Lib "user32" (ByVal wFormat As Integer) As Long

'Close the clipboard
Private Declare Function CloseClipboard Lib "user32" () As Long

'Convert the handle into an OLE IPicture interface.
Private Declare Function OleCreatePictureIndirect Lib "olepro32.dll" (PicDesc As uPicDesc, RefIID As GUID, ByVal fPictureOwnsHandle As Long, IPic As IPicture) As Long

'Create our own copy of the metafile, so it doesn't get wiped out by subsequent clipboard updates.
Declare Function CopyEnhMetaFile Lib "gdi32" Alias "CopyEnhMetaFileA" (ByVal hemfSrc As Long, ByVal lpszFile As String) As Long

'Create our own copy of the bitmap, so it doesn't get wiped out by subsequent clipboard updates.
Declare Function CopyImage Lib "user32" (ByVal handle As Long, ByVal un1 As Long, ByVal n1 As Long, ByVal n2 As Long, ByVal un2 As Long) As Long

'The API format types we're interested in
Const CF_BITMAP = 2
Const CF_PALETTE = 9
Const CF_ENHMETAFILE = 14
Const IMAGE_BITMAP = 0
Const LR_COPYRETURNORG = &H4

''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
''' Subroutine: PastePicture
'''
''' Purpose:    Get a Picture object showing whatever's on the clipboard.
'''
''' Arguments:  lXlPicType - The type of picture to create.  Can be one of:
'''                          xlPicture to create a metafile (default)
'''                          xlBitmap to create a bitmap
'''
''' Date        Developer           Action
''' --------------------------------------------------------------------------
''' 30 Oct 98   Stephen Bullen      Created
''' 15 Nov 98   Stephen Bullen      Updated to create our own copies of the clipboard images
'''

Function PastePicture(Optional lXlPicType As Long = xlPicture) As IPicture

'Some pointers
Dim h As Long, hPicAvail As Long, hPtr As Long, hPal As Long, lPicType As Long, hCopy As Long

'Convert the type of picture requested from the xl constant to the API constant
lPicType = IIf(lXlPicType = xlBitmap, CF_BITMAP, CF_ENHMETAFILE)

'Check if the clipboard contains the required format
hPicAvail = IsClipboardFormatAvailable(lPicType)

If hPicAvail <> 0 Then
    'Get access to the clipboard
    h = OpenClipboard(0&)

    If h > 0 Then
        'Get a handle to the image data
        hPtr = GetClipboardData(lPicType)

        'Create our own copy of the image on the clipboard, in the appropriate format.
        If lPicType = CF_BITMAP Then
            hCopy = CopyImage(hPtr, IMAGE_BITMAP, 0, 0, LR_COPYRETURNORG)
        Else
            hCopy = CopyEnhMetaFile(hPtr, vbNullString)
        End If

        'Release the clipboard to other programs
        h = CloseClipboard

        'If we got a handle to the image, convert it into a Picture object and return it
        If hPtr <> 0 Then Set PastePicture = CreatePicture(hCopy, 0, lPicType)
    End If
End If

End Function


''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
''' Subroutine: CreatePicture
'''
''' Purpose:    Converts a image (and palette) handle into a Picture object.
'''
'''             Requires a reference to the "OLE Automation" type library
'''
''' Arguments:  None
'''
''' Date        Developer           Action
''' --------------------------------------------------------------------------
''' 30 Oct 98  Stephen Bullen      Created
'''

Private Function CreatePicture(ByVal hPic As Long, ByVal hPal As Long, ByVal lPicType) As IPicture

' IPicture requires a reference to "OLE Automation"
Dim r As Long, uPicInfo As uPicDesc, IID_IDispatch As GUID, IPic As IPicture

'OLE Picture types
Const PICTYPE_BITMAP = 1
Const PICTYPE_ENHMETAFILE = 4

' Create the Interface GUID (for the IPicture interface)
With IID_IDispatch
    .Data1 = &H7BF80980
    .Data2 = &HBF32
    .Data3 = &H101A
    .Data4(0) = &H8B
    .Data4(1) = &HBB
    .Data4(2) = &H0
    .Data4(3) = &HAA
    .Data4(4) = &H0
    .Data4(5) = &H30
    .Data4(6) = &HC
    .Data4(7) = &HAB
End With

' Fill uPicInfo with necessary parts.
With uPicInfo
    .Size = Len(uPicInfo)                                                   ' Length of structure.
    .Type = IIf(lPicType = CF_BITMAP, PICTYPE_BITMAP, PICTYPE_ENHMETAFILE)  ' Type of Picture
    .hPic = hPic                                                            ' Handle to image.
    .hPal = IIf(lPicType = CF_BITMAP, hPal, 0)                              ' Handle to palette (if bitmap).
End With

' Create the Picture object.
r = OleCreatePictureIndirect(uPicInfo, IID_IDispatch, True, IPic)

' If an error occured, show the description
If r <> 0 Then Debug.Print "Create Picture: " & fnOLEError(r)

' Return the new Picture object.
Set CreatePicture = IPic

End Function

''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
''' Subroutine: fnOLEError
'''
''' Purpose:    Gets the message text for standard OLE errors
'''
''' Arguments:  None
'''
''' Date        Developer           Action
''' --------------------------------------------------------------------------
''' 30 Oct 98   Stephen Bullen      Created
'''

Private Function fnOLEError(lErrNum As Long) As String

'OLECreatePictureIndirect return values
Const E_ABORT = &H80004004
Const E_ACCESSDENIED = &H80070005
Const E_FAIL = &H80004005
Const E_HANDLE = &H80070006
Const E_INVALIDARG = &H80070057
Const E_NOINTERFACE = &H80004002
Const E_NOTIMPL = &H80004001
Const E_OUTOFMEMORY = &H8007000E
Const E_POINTER = &H80004003
Const E_UNEXPECTED = &H8000FFFF
Const S_OK = &H0

Select Case lErrNum
Case E_ABORT
    fnOLEError = " Aborted"
Case E_ACCESSDENIED
    fnOLEError = " Access Denied"
Case E_FAIL
    fnOLEError = " General Failure"
Case E_HANDLE
    fnOLEError = " Bad/Missing Handle"
Case E_INVALIDARG
    fnOLEError = " Invalid Argument"
Case E_NOINTERFACE
    fnOLEError = " No Interface"
Case E_NOTIMPL
    fnOLEError = " Not Implemented"
Case E_OUTOFMEMORY
    fnOLEError = " Out of Memory"
Case E_POINTER
    fnOLEError = " Invalid Pointer"
Case E_UNEXPECTED
    fnOLEError = " Unknown Error"
Case S_OK
    fnOLEError = " Success!"
End Select

End Function