Attribute VB_Name = "Module1"
Option Explicit

Public Const CCHDEVICENAME = 32
Public Const CCHFORMNAME = 32
Public Const DM_PELSWIDTH = &H80000
Public Const DM_PELSHEIGHT = &H100000
Public Const DM_BITSPERPEL = &H40000

Type DEVMODE
    dmDeviceName As String * CCHDEVICENAME
    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 * CCHFORMNAME
    dmUnusedPadding As Integer
    dmBitsPerPel As Integer
    dmPelsWidth As Long
    dmPelsHeight As Long
    dmDisplayFlags As Long
    dmDisplayFrequency As Long
End Type

Declare Function lstrcpy& Lib "kernel32" Alias "lstrcpyA" (lpString1 As Any, lpString2 As Any)
Declare Function ChangeDisplaySettings Lib "User32" Alias "ChangeDisplaySettingsA" (ByVal lpDevMode As Long, ByVal dwflags As Long) As Long


'========================================================
' 函數: SetDisplayMode
'
' 功能: 設置屏幕分辨率
'
' 入口: Width           屏幕寬
'       Height          屏幕高
'       ColorDepth      屏幕色深
'
Function SetDisplayMode&(ByVal Width&, _
                         ByVal Height&, _
                         ByVal ColorDepth&)
'-------------------------------------------------------
    Dim NewDevMode As DEVMODE
    Dim pDevmode As Long
    
    With NewDevMode
        .dmSize = 122
        '
        If ColorDepth& = -1 Then
            .dmFields = DM_PELSWIDTH Or _
                        DM_PELSHEIGHT
        Else
            .dmFields = DM_PELSWIDTH Or _
                        DM_PELSHEIGHT Or _
                        DM_BITSPERPEL
        End If
        
        .dmPelsWidth = Width&
        .dmPelsHeight = Height&
    
        If ColorDepth& <> -1 Then
            .dmBitsPerPel = ColorDepth&
        End If
    End With
    
    pDevmode = lstrcpy(NewDevMode, NewDevMode)
    
    SetDisplayMode = ChangeDisplaySettings(pDevmode, 0)
'-------------------------------------------------------
End Function
'========================================================