by ScAnFrEaK (1 Submission)
Category: Miscellaneous
Compatability: Visual Basic 3.0
Difficulty: Unknown Difficulty
Date Added: Wed 3rd February 2021
Rating: 
(3 Votes)
This Function will change your Windows Resolution. It is very simple, and it does what most Resolution Change Functions don't do, it changes the the Bits Per Pixels as well as the Screen Width and Height.
Inputs
Dim RetValue As Integer
RetValue = ChangeRes(800, 600, 32)
Code Returns
1 = Resolution Successfully Changed
0 = Resolution Was Not Changed
API DeclarationsPrivate 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_BITSPERPEL = &H60000
Private Const DM_PELSWIDTH = &H80000
Private Const DM_PELSHEIGHT = &H100000
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
VBcodersFunction ChangeRes(Width As Single, Height As Single, BPP As Integer) As Integer
On Error GoTo ERROR_HANDLER
Dim DevM As DEVMODE, I As Integer, ReturnVal As Boolean, _
RetValue, OldWidth As Single, OldHeight As Single, _
OldBPP As Integer
Call EnumDisplaySettings(0&, -1, DevM)
OldWidth = DevM.dmPelsWidth
OldHeight = DevM.dmPelsHeight
OldBPP = DevM.dmBitsPerPel
I = 0
Do
ReturnVal = EnumDisplaySettings(0&, I, DevM)
I = I + 1
Loop Until (ReturnVal = False)
DevM.dmFields = DM_PELSWIDTH Or DM_PELSHEIGHT Or DM_BITSPERPEL
DevM.dmPelsWidth = Width
DevM.dmPelsHeight = Height
DevM.dmBitsPerPel = BPP
Call ChangeDisplaySettings(DevM, 1)
RetValue = MsgBox("Do You Wish To Keep Your Screen Resolution To " & Width & "x" & Height & " - " & BPP & " BPP?", vbQuestion + vbOKCancel, "Change Resolution Confirm:")
If RetValue = vbCancel Then
DevM.dmPelsWidth = OldWidth
DevM.dmPelsHeight = OldHeight
DevM.dmBitsPerPel = OldBPP
Call ChangeDisplaySettings(DevM, 1)
MsgBox "Old Resolution(" & OldWidth & " x " & OldHeight & ", " & OldBPP & " Bit) Successfully Restored!", vbInformation + vbOKOnly, "Resolution Confirm:"
ChangeRes = 0
Else
ChangeRes = 1
End If
Exit Function
ERROR_HANDLER:
ChangeRes = 0
End Function
