Question

VB中关于PNG图片问题

这段代码做出类似Photoshop的启动效果
可惜要占用大量内存.请高手对代码优化..真是搞不明白!!
或者给出其它类似效果的方法...
以下窗体,API声明省去了 因为太多了 呵呵
Dim mDC As Long
Dim mainBitmap As Long
Dim blendFunc32bpp As BLENDFUNCTION
Dim token As Long
Dim oldBitmap As Long

Private Sub Form_DblClick()

Unload Me

End Sub

Private Sub Form_Load()

Dim GpInput As GdiplusStartupInput
GpInput.GdiplusVersion = 1

If GdiplusStartup(token, GpInput) <> 0 Then
MsgBox "Fehler bem laden von GDI+!", vbCritical
Unload Me
End If

MakeTrans (App.Path & "\splash.png")

End Sub

Private Sub Form_Unload(Cancel As Integer)

Call GdiplusShutdown(token)
SelectObject mDC, oldBitmap
DeleteObject mainBitmap
DeleteObject oldBitmap
DeleteDC mDC

End Sub

Private Function MakeTrans(pngPath As String) As Boolean

Dim tempBI As BITMAPINFO
Dim tempBlend As BLENDFUNCTION
Dim lngHeight As Long, lngWidth As Long
Dim curWinLong As Long
Dim img As Long
Dim graphics As Long
Dim winSize As Size
Dim srcPoint As POINTAPI

With tempBI.bmiHeader
.biSize = Len(tempBI.bmiHeader)
.biBitCount = 32
.biHeight = Me.ScaleHeight
.biWidth = Me.ScaleWidth
.biPlanes = 1
.biSizeImage = .biWidth * .biHeight * (.biBitCount / 8)
End With
mDC = CreateCompatibleDC(Me.hdc)
mainBitmap = CreateDIBSection(mDC, tempBI, DIB_RGB_COLORS, ByVal 0, 0, 0)
oldBitmap = SelectObject(mDC, mainBitmap)

Call GdipCreateFromHDC(mDC, graphics)
Call GdipLoadImageFromFile(StrConv(pngPath, vbUnicode), img)
Call GdipGetImageHeight(img, lngHeight)
Call GdipGetImageWidth(img, lngWidth)
Call GdipDrawImageRect(graphics, img, 0, 0, lngWidth, lngHeight)

curWinLong = GetWindowLong(Me.hwnd, GWL_EXSTYLE)

SetWindowLong Me.hwnd, GWL_EXSTYLE, curWinLong Or WS_EX_LAYERED
SetWindowPos Me.hwnd, HWND_TOPMOST, 0, 0, 0, 0, SWP_NOMOVE Or SWP_NOSIZE

srcPoint.x = 0
srcPoint.y = 0
winSize.cx = Me.ScaleWidth
winSize.cy = Me.ScaleHeight

With blendFunc32bpp
.AlphaFormat = AC_SRC_ALPHA
.BlendFlags = 0
.BlendOp = AC_SRC_OVER
.SourceConstantAlpha = 255
End With

Call GdipDisposeImage(img)
Call GdipDeleteGraphics(graphics)
Call UpdateLayeredWindow(Me.hwnd, Me.hdc, ByVal 0&, winSize, mDC, srcPoint, 0, blendFunc32bpp, ULW_ALPHA)

End Function
图片只有114K 程序运行要占用240MB内存...问题就在这

Answer 1

把图片压缩下吧，代码没啥毛病，问题是图片全部加载进内存了。

可以使用jpg格式的压缩图片，会减少很多内存消耗

Answer 2

还没看代码，但是请先检查一下用过的对象有没有释放