Keskustelu: Ohjelmointikysymykset: VB6: Näyttöasetusten vaihto

 Public Structure DEVMODE
        <System.Runtime.InteropServices.MarshalAsAttribute(System.Runtime.InteropServices.UnmanagedType.ByValTStr, SizeConst:=32)> Dim dmDeviceName As String
        Dim dmSpecVersion As Short
        Dim dmDriverVersion As Short
        Dim dmSize As Short
        Dim dmDriverExtra As Short
        Dim dmFields As Integer
        Dim dmOrientation As Short
        Dim dmPaperSize As Short
        Dim dmPaperLength As Short
        Dim dmPaperWidth As Short
        Dim dmScale As Short
        Dim dmCopies As Short
        Dim dmDefaultSource As Short
        Dim dmPrintQuality As Short
        Dim dmColor As Short
        Dim dmDuplex As Short
        Dim dmYResolution As Short
        Dim dmTTOption As Short
        Dim dmCollate As Short
        <System.Runtime.InteropServices.MarshalAsAttribute(System.Runtime.InteropServices.UnmanagedType.ByValTStr, SizeConst:=32)> Dim dmFormName As String
        Dim dmUnusedPadding As Short
        Dim dmBitsPerPel As Short
        Dim dmPelsWidth As Integer
        Dim dmPelsHeight As Integer
        Dim dmDisplayFlags As Short
        Dim dmDisplayFrequency As Long
    End Structure
    Private Declare Function EnumDisplaySettings Lib "user32" Alias "EnumDisplaySettingsA" (ByVal lpszDeviceName As Integer, ByVal iModeNum As Integer, ByRef lpDevMode As DEVMODE) As Integer
    Private Declare Function ChangeDisplaySettings Lib "user32" Alias "ChangeDisplaySettingsA" (lpDevMode As DEVMODE, ByVal dwFlags As Integer) As Integer


'seuraava koodi on yhdessä aliohjelmassa:
Try
            Call EnumDisplaySettings(0&, -1&, DevOrg)
            Dim DevNew As DEVMODE = DevOrg
            DevNew.dmPelsWidth = 640
            DevNew.dmPelsHeight = 480
            DevNew.dmBitsPerPel = 16
            DevNew.dmDisplayFrequency = 75
            Dim test As Long
            test = ChangeDisplaySettings(DevNew, &H4) 'tällä rivillä tökkää
            Select Case test
                Case 0
                    Call ChangeDisplaySettings(DevNew, &H1)
                    'näytön asetukset vaihdettu
                Case Else
                    'näytön asetuksia ei vaihdettu
            End Select
        Catch ex As Exception
            MsgBox(ex.Message, 16, "Error!")
        End Try