picture缩略图调用出现 参数不可选

asd888

源代码

Sub GdipLoadZoomImage(strFileName As String, PBox As PictureBox)
On Error Resume Next
Dim gdip_Token As Long
Dim gdip_Image As Long
Dim gdip_Graphics As Long
Dim lRet As Long
Dim iW As Long
Dim iH As Long
Dim pW As Single
Dim pH As Single
Dim GpInput As GdiplusStartupInput
GpInput.GdiplusVersion = 1
If GdiplusStartup(gdip_Token, GpInput) <> 0 Then Exit Sub
PBox.Cls
GdipLoadImageFromFile StrPtr(strFileName), gdip_Image
GdipGetImageWidth gdip_Image, iW
GdipGetImageHeight gdip_Image, iH
If gdip_Image Then GdipDisposeImage gdip_Image
If iW <> 0 And iH <> 0 Then
pW = PBox.ScaleWidth
pH = PBox.ScaleHeight
GetImageZoomSize iW, iH, pW, pH
PBox.Cls
If GdipCreateFromHDC(PBox.hDC, gdip_Graphics) = 0 Then
GdipLoadImageFromFile StrPtr(strFileName), gdip_Image
lRet = GdipDrawImageRect(gdip_Graphics, gdip_Image, _
(PBox.ScaleWidth - pW) \ 2, (PBox.ScaleHeight - pH) \ 2, pW, pH) '绘图
If gdip_Image Then GdipDisposeImage gdip_Image

GdipDeleteGraphics gdip_Graphics
End If
End If
GdiplusShutdown gdip_Token
End Sub

Function GetImageZoomSize(ByVal nSrcWidth As Integer, ByVal nSrcHeight As Integer, ByRef nDstWidth As Integer, ByRef nDstHeight As Integer)
        If nSrcWidth / nSrcHeight < nDstWidth / nDstHeight Then
            nDstWidth = nDstHeight * (nSrcWidth / nSrcHeight)
        Else
            nDstHeight = nDstWidth * (nSrcHeight / nSrcWidth)
        End If
    End Function