Операции "копировать", "вырезать", "вставить".

Копировать:
On Error Resume Next
Clipboard.SetText ВАШ ТЕКСТБОКС.SelText

Вырезать:
On Error Resume Next
Clipboard.SetText ВАШ ТЕКСТБОКС.SelText
ВАШ ТЕКСТБОКС.SelText = vbNullString

Вставить:
On Error Resume Next
ВАШ ТЕКСТБОКС.SelText = Clipboard.GetText

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Открытие стандартного диалогового окна выбора каталога.

Для работы примера на форме Form1 поставьте кнопку Сommand1 и текстбокс Text1.

В модуле:
Public Type BROWSEINFO
hOwner As Long
pidlRoot As Long
pszDisplayName As String
lpszTitle As String
ulFlags As Long
lpfn As Long
lParam As Long
iImage As Long
End Type

Public Declare Function SHGetPathFromIDList Lib "shell32.dll" Alias "SHGetPathFromIDListA" _
(ByVal pidl As Long, ByVal pszPath As String) As Long
Public Declare Function SHBrowseForFolder Lib "shell32.dll" Alias "SHBrowseForFolderA" _
(lpBrowseInfo As BROWSEINFO) As Long

Public Const BIF_RETURNONLYFSDIRS = &H1

В форме:
Private Sub Command1_Click()
Dim myBrowseInfo As BROWSEINFO
Dim execNumderDir As Boolean
Dim NumderDir As Long
Dim pos As Integer
Dim myPath_512 As String

With myBrowseInfo
.hOwner = Me.hWnd
.pidlRoot = 0&
.lpszTitle = "Выберите директорию"
.ulFlags = BIF_RETURNONLYFSDIRS
End With

NumderDir& = SHBrowseForFolder(myBrowseInfo)
myPath_512$ = Space$(512)
execNumderDir = SHGetPathFromIDList(ByVal NumderDir&, ByVal myPath_512$)

If execNumderDir Then
pos = InStr(myPath_512$, Chr$(0))
myPath = Left(myPath_512$, pos - 1)
Else
myPath = ""
End If
Text1.Text = myPath
End Sub

---

Определение разрешения и количества цветов дисплея.

В модуле:
Declare Function GetDeviceCaps Lib "gdi32" (ByVal hDC As Long, _
ByVal nIndex As Long) As Long
Declare Function GetDesktopWindow Lib "user32" () As Long
Declare Function GetDC Lib "user32" (ByVal hwnd As Long) As Long
Declare Function ReleaseDC Lib "user32" (ByVal hwnd As Long, ByVal hDC As Long) As Long
Public Const HORZRES = 8
Public Const VERTRES = 10
Public Const BITSPIXEL = 12

Public Sub GetVideoMode(ByRef Width As Long, ByRef Height As Long, ByRef Depth As Long)
Dim hDC As Long
hDC = GetDC(GetDesktopWindow())
Width = GetDeviceCaps(hDC, HORZRES)
Height = GetDeviceCaps(hDC, VERTRES)
Depth = GetDeviceCaps(hDC, BITSPIXEL)
ReleaseDC GetDesktopWindow(), hDC
End Sub

Использование:
Dim Width As Long, Height As Long, Depth As Long
GetVideoMode Width, Height, Depth

Примечание: В переменной Depth возвращается не количество цветов, а количество битов на один пиксель. Т.е. 16 цветам соответствует 4 бита на пиксель, 256 - 8 бит, 65536 - 16 бит и т.д.

Изменение текущего роазрешения экрана и кол-ва цветов

В модуле:
Public Const DM_BITSPERPEL = &H40000
Public Const DM_PELSWIDTH = &H80000
Public Const DM_PELSHEIGHT = &H100000
Public Const CCHDEVICENAME = 32
Public Const CCHFORMNAME = 32
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 ChangeDisplaySettings Lib "user32.dll" Alias _
"ChangeDisplaySettingsA" (lpDevMode As DEVMODE, ByVal dwFalgs As Long) As Long

Public Sub SetVideoMode(Width As Long, height As Long, Depth As Long)
Dim dm As DEVMODE
dm.dmPelsWidth = Width
dm.dmPelsHeight = height
dm.dmBitsPerPel = Depth
dm.dmSize = Len(dm)
dm.dmFields = DM_PELSWIDTH + DM_PELSHEIGHT + DM_BITSPERPEL
ChangeDisplaySettings dm, 0
End Sub
Использование:
SetVideoMode 1024, 768, 8 'Устанавливает видеорежим 1024x768 c 256 цветами.

Примечание: Указывается не количество цветов, а количество битов на один пиксель. Т.е. 16 цветам соответствует 4 бита на пиксель, 256 - 8 бит, 65536 - 16 бит и т.д.