Microsoft Windows starts screen savers through the System-menu box on a form. The System-menu box is also known as the Control-menu box in Visual Basic. You can send Windows messages to the Control-menu box by using the SendMessage Windows API (application programming interface) function.
Add the following to the general declarations section of Form1, or to a .Bas module file, in Visual Basic:
' The following Declare statement must be on one, single line: Declare Function SendMessage Lib "User" (ByVal hWnd As Integer, ByVal wMsg As Integer, ByVal wParam As Integer, lParam As Any) As Long
In the following example, a command button starts the Form1 screen saver:
Sub Command1_Click () Dim result As Long Const WM_SYSCOMMAND = &H112
Const SC_SCREENSAVE = &HF140 result = SendMessage(Form1.hWnd, WM_SYSCOMMAND, SC_SCREENSAVE, 0&) End Sub