(Not tested):

Option Explicit
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA"
(ByVal hWnd As System.IntPtr, ByVal wMsg As Integer, ByVal wParam As
Integer, ByVal lParam As Integer) As Integer

Const WM_SYSCOMMAND As Integer= &H112
Const SC_MONITORPOWER As Integer= &HF170

Private Sub Command1_Click() Handles Command1.Click
SendMessage Me.Handle, WM_SYSCOMMAND, SC_MONITORPOWER, -1
End Sub

Private Sub Command2_Click() Handles Command2.Click
SendMessage Me.Handle, WM_SYSCOMMAND, SC_MONITORPOWER, 0
End Sub

Basically, "Long" -> "Integer", hwnd-> Handle and handles are declared as
IntPtr. As for "As Any", you can declare as many overloaded SendMessage
functions as needed varying the last parameter to meet your needs, "As Any"
is no longer needed.