[VB6 and API] - Convert a hdc to long variable

[joaquim]

i build 1 function for convert hdc to long variable:

Public Function ConvertPicturetoLong(PicControl As PictureBox) As Long
    Dim mdc As Long
    Dim mBMP As Long
    mdc = CreateCompatibleDC(PicControl.hDC)
    mBMP = CreateCompatibleBitmap(PicControl.hDC, PicControl.ScaleWidth, PicControl.ScaleHeight)
    SelectObject mdc, mBMP
    ConvertPicturetoLong = mBMP
    DeleteObject mBMP
    DeleteDC mdc
End Function

but i belive that isn't work, because when i do:

dim s as long
 s = ConvertPicturetoLong(PicAnimation(PicAnimation.Count - 1))
        PicAnimation(PicAnimation.Count - 1).Picture = Nothing
        Debug.Print BitBlt(PicAnimation(PicAnimation.Count - 1), 0, 0, UserControl.Width, UserControl.Height, s, 0, 0, vbSrcCopy)

because the bitblt() give me 0(zero). what isn't right?