Private Declare Function GetDeviceCaps Lib "gdi32" (ByVal hdc As Long, ByVal nIndex As Long) As Long Private Declare Function ChangeDisplaySettings Lib "user32" Alias "ChangeDisplaySettingsA" (lpDevMode As Any, ByVal dwflags As Long) As Long Private Const CCDEVICENAME As Long = 32 Private Const CCFORMNAME As Long = 32 Private Const DM_BITSPERPEL As Long = &H40000 Private Const DM_PELSWIDTH As Long = &H80000 Private Const DM_PELSHEIGHT As Long = &H100000 Private Const DM_DISPLAYFLAGS As Long = &H200000 Private Const DM_DISPLAYFREQUENCY = &H400000 Private Const CDS_FORCE As Long = &H80000000 Private Const BITSPIXEL As Long = 12 Private Const HORZRES As Long = 8 Private Const VERTRES As Long = 10 Private Const VREFRESH = 116 Private Type DEVMODE    dmDeviceName      As String * CCDEVICENAME    dmSpecVersion     As Integer    dmDriverVersion   As Integer    dmSize            As Integer    dmDriverExtra     As Integer    dmFields          As Long    dmOrientation     As Integer    dmPaperSize       As Integer    dmPaperLength     As Integer    dmPaperWidth      As Integer    dmScale           As Integer    dmCopies          As Integer    dmDefaultSource   As Integer    dmPrintQuality    As Integer    dmColor           As Integer    dmDuplex          As Integer    dmYResolution     As Integer    dmTTOption        As Integer    dmCollate         As Integer    dmFormName        As String * CCFORMNAME    dmUnusedPadding   As Integer    dmBitsPerPel      As Integer    dmPelsWidth       As Long    dmPelsHeight      As Long    dmDisplayFlags    As Long    dmDisplayFrequency As Long End Type Private Sub cmdChangeDesktopMode_Click()     Dim DM As DEVMODE     With DM        .dmPelsWidth = CInt(txtNewWidth.Text)        .dmPelsHeight = CInt(txtNewHeight.Text)        .dmBitsPerPel = CInt(txtNewColor.Text)        .dmDisplayFrequency = CInt(txtNewFreq.Text)        .dmFields = DM_PELSWIDTH Or DM_PELSHEIGHT Or DM_BITSPERPEL Or DM_DISPLAYFREQUENCY        .dmSize = LenB(DM)     End With     If ChangeDisplaySettings(DM, CDS_FORCE) <> 0 Then         MsgBox "错误!不支持此模式！"     End If End Sub Private Sub Form_Load()    txtOldWidth.Text = GetDeviceCaps(Me.hdc, HORZRES)    txtOldHeight.Text = GetDeviceCaps(Me.hdc, VERTRES)    txtOldColor.Text = GetDeviceCaps(Me.hdc, BITSPIXEL)    txtOldFreq.Text = GetDeviceCaps(Me.hdc, VREFRESH) End Sub