vb6，计算器嵌入exe

Option Explicit
Private Declare Function SetFocusA Lib "user32" Alias "SetFocus" (ByVal hwnd As Long) As Long
Private Declare Function SetParent Lib "user32.dll" (ByVal hWndChild As Long, ByVal hWndNewParent As Long) As Long
Private Declare Function SetWindowLong Lib "user32.dll" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
Private Declare Function FindWindow Lib "user32.dll" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long

Private Const WS_EX_MDICHILD As Long = &H40&
Private Const GWL_STYLE = (-16)
Private Const GWL_EXSTYLE As Long = (-20)
Private Const WS_CHILD = &H40000000
Private Const WS_CHILDWINDOW = (WS_CHILD)
Dim lngCalculator As Long

'把计算器作为子窗体
Private Sub Form_Load()

Dim lngStyle As Long
Dim lngExStyle As Long
Shell "calc.exe", vbNormalFocus
lngCalculator = FindWindow(vbNullString, "计算器")
If lngCalculator > 0 Then
SetParent lngCalculator, Me.hwnd
SetWindowLong lngCalculator, GWL_EXSTYLE, WS_EX_MDICHILD
End If
End Sub