i have code for change the screen resolution and see the actual screen resolution. but can i see the possibles resolutions?
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i have code for change the screen resolution and see the actual screen resolution. but can i see the possibles resolutions?
sorry my limited english... i was talking about: Displays Modes;)
now that i found the code i can share it;)
heres how change the resolution:
and heres how catch the possibles card\monitor resolutions:Code:'The EnumDisplaySettings function retrieves information about one of the graphics modes for a display device
Private Declare Function EnumDisplaySettings Lib "user32" Alias "EnumDisplaySettingsA" (ByVal lpszDeviceName As Long, ByVal iModeNum As Long, lpDevMode As Any) As Boolean
'The ChangeDisplaySettings function changes the settings of the default display device to the specified graphics mode.
Private Declare Function ChangeDisplaySettings Lib "user32" Alias "ChangeDisplaySettingsA" (lpDevMode As Any, ByVal dwflags As Long) As Long
'Logs off the interactive user, shuts down the system, or shuts down and restarts the system.
Private Declare Function ExitWindowsEx Lib "user32" (ByVal uFlags As Long, ByVal dwReserved As Long) As Long
'The GetDeviceCaps function retrieves device-specific information for the specified device.
Private Declare Function GetDeviceCaps Lib "gdi32" (ByVal hdc As Long, ByVal nIndex As Long) As Long
'The CreateDC function creates a device context (DC) for a device using the specified name
Private Declare Function CreateDC Lib "gdi32" Alias "CreateDCA" (ByVal lpDriverName As String, ByVal lpDeviceName As String, ByVal lpOutput As String, ByVal lpInitData As Any) As Long
'The DeleteDC function deletes the specified device context (DC).
Private Declare Function DeleteDC Lib "gdi32" (ByVal hdc As Long) As Long
'Sends the specified message to a window or windows
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Private Const EWX_LOGOFF = 0 'Log Off
Private Const EWX_SHUTDOWN = 1 'Shut Down
Private Const EWX_REBOOT = 2 'Reboot
Private Const EWX_FORCE = 4 'Force Reboot
Private Const CCDEVICENAME = 32 'Device Name
Private Const CCFORMNAME = 32 'Name of the Form to use; For Example, "Letter" or "Legal"
Private Const DM_BITSPERPEL = &H40000 'Specifies the color resolution
Private Const DM_PELSWIDTH = &H80000 'Specifies the width, in pixels, of the visible device surface.
Private Const DM_PELSHEIGHT = &H100000 'Specifies the height, in pixels, of the visible device surface
Private Const BITSPIXEL = 12 'Bits per Pixel Setting
Private Const CDS_UPDATEREGISTRY = &H1 'Update Registry
Private Const CDS_TEST = &H4 'Allows an application to determine which graphics modes are actually valid, without causing the system to change to the settings.
Private Const DISP_CHANGE_SUCCESSFUL = 0 'Was The Change Successful?
Private Const DISP_CHANGE_RESTART = 1 'Does Change Require Restart?
Private Const WM_DISPLAYCHANGE = &H7E 'Display Has Changed
Private Const HWND_BROADCAST = &HFFFF& 'Broadcast to all Windows
'The DEVMODE data structure contains information about the initialization and environment of a printer or a display device.
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
Public Sub ChangeResolution(X As Long, Y As Long, BitsPerPixel As Long)
Dim DevM As DEVMODE 'Contains DEVMODE Info
Dim ScreenInfo As Long 'Screen Info
Dim lResult As Long 'Result of Functions
Dim intAnsw As VbMsgBoxResult 'Messagebox Question
'Get DisplaySettings Information
lResult = EnumDisplaySettings(0&, 0&, DevM)
'Change Pixel Settings
DevM.dmFields = DM_PELSWIDTH Or DM_PELSHEIGHT Or DM_BITSPERPEL
DevM.dmPelsWidth = X 'Screen Width
DevM.dmPelsHeight = Y 'Screen Height
DevM.dmBitsPerPel = BitsPerPixel 'Can Be 4, 8, 16, 24, 32
'Try To Change Display Settings
lResult = ChangeDisplaySettings(DevM, CDS_TEST)
'If Succesful
Select Case lResult&
'Requires A Restart
Case DISP_CHANGE_RESTART
intAnsw = MsgBox("You Must Restart To Apply These Changes." & _
vbCrLf & "Restart Now ?", _
vbYesNo, "Screen Resolution")
If intAnsw = vbYes Then 'Restart
lResult& = ExitWindowsEx(EWX_REBOOT, 0&)
End If
'Successful Without The Need Of Restart
Case DISP_CHANGE_SUCCESSFUL
lResult = ChangeDisplaySettings(DevM, CDS_UPDATEREGISTRY)
ScreenInfo = Y * 2 ^ 16 + X
'Notify all the windows of the screen resolution change
SendMessage HWND_BROADCAST, WM_DISPLAYCHANGE, ByVal BitsPerPixel, ByVal ScreenInfo
'MsgBox "Screen Resolution Changed", vbInformation, "Screen Resolution Changed"
Case Else
MsgBox "Mode Not Supported", vbOKOnly + vbSystemModal, "Error"
End Select
End Sub
Private Sub Form_Load()
Dim nDC As Long
If blnFirstOldResolution = False Then
'Retrieve Screen's Current Resolution
OldX = Screen.Width / Screen.TwipsPerPixelX
OldY = Screen.Height / Screen.TwipsPerPixelY
'Create Device Context Compatible With Screen
nDC = CreateDC("DISPLAY", vbNullString, vbNullString, ByVal 0&)
lngOldBits = GetDeviceCaps(nDC, BITSPIXEL)
'Change Resolution
ChangeResolution 1024, 768, lngOldBits
blnFirstOldResolution = True ' these variable is for don't lose the desktop resolution
End If
End Sub
Private Sub Form_Unload(Cancel As Integer)
'Restore Old Resolution
ChangeResolution OldX, OldY, GetDeviceCaps(nDC, BITSPIXEL)
'Delete Device Context
DeleteDC nDC
End Sub
these code shows the width and height, but can be showed the bits too;)Code:Private Declare Function EnumDisplaySettings Lib "user32" Alias "EnumDisplaySettingsA" (ByVal lpszDeviceName As Long, ByVal iModeNum As Long, lpDevMode As Any) As Boolean
Private Declare Function ChangeDisplaySettings Lib "user32" Alias "ChangeDisplaySettingsA" (lpDevMode As Any, ByVal dwflags As Long) As Long
Private Const CCDEVICENAME = 32
Private Const CCFORMNAME = 32
Private Const DM_PELSWIDTH = &H80000
Private Const DM_PELSHEIGHT = &H100000
Private Const DM_BITSPERPEL = &H40000
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
Dim DevM() As DEVMODE
Public Sub InicializarDevM()
Dim DevM() As DEVMODE
Dim Tmp1 As Boolean
Dim Tmp2 As Integer
Dim Tmp3 As Integer
Dim Tmp4 As Integer
Dim blntrue As Boolean
Dim i As Integer
Dim strResolution As String
Tmp2 = 0
Tmp3 = 0
Tmp4 = 0
Do
ReDim Preserve DevM(0 To Tmp2)
Tmp1 = EnumDisplaySettings(0&, Tmp2, DevM(Tmp2))
Tmp1 = EnumDisplaySettings(0&, Tmp3, DevM(Tmp3))
Tmp1 = EnumDisplaySettings(0&, Tmp4, DevM(Tmp4))
If Tmp1 Then
strResolution = DevM(Tmp2).dmPelsWidth & "x" & DevM(Tmp3).dmPelsHeight
For i = 0 To cboResolution.ListCount - 1
If cboResolution.List(i) = strResolution Then
blntrue = True
Exit For
Else
blntrue = False
End If
Next i
If blntrue = False Then
cboResolution.AddItem strResolution
cboRes1.AddItem DevM(Tmp2).dmPelsWidth
cboRes2.AddItem DevM(Tmp3).dmPelsHeight
End If
End If
Tmp2 = Tmp2 + 1
Tmp3 = Tmp3 + 1
Tmp4 = Tmp4 + 1
Loop Until (Tmp1 = False)
End Sub