Option Explicit
Private Sub Form_Load()
If App.PrevInstance Then
ActivatePrevInstance
End If
End Sub
' Thêm một module
' Paste đoạn code vào
Option Explicit
Public Const GW_HWNDPREV = 3
Declare Function OpenIcon Lib user32 (ByVal hwnd As Long) As Long
Declare Function FindWindow Lib user32 Alias FindWindowA (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Declare Function GetWindow Lib user32 (ByVal hwnd As Long, ByVal wCmd As Long) As Long
Declare Function SetForegroundWindow Lib user32 (ByVal hwnd As Long) As Long
Sub ActivatePrevInstance()
Dim OldTitle As String
Dim PrevHndl As Long
Dim result As Long
OldTitle = App.Title
App.Title = unwanted instance
PrevHndl = FindWindow(ThunderRTMain, OldTitle)
If PrevHndl = 0 Then
PrevHndl = FindWindow(ThunderRT5Main, OldTitle)
End If
If PrevHndl = 0 Then
PrevHndl = FindWindow(ThunderRT6Main, OldTitle)
End If
If PrevHndl = 0 Then
Exit Sub
End If
PrevHndl = GetWindow(PrevHndl, GW_HWNDPREV)
result = OpenIcon(PrevHndl)
result = SetForegroundWindow(PrevHndl)
End
End Sub