用 API 禁止关闭窗口禁止最小化后怎么解除

Public Function DisableClose(ByVal hwnd, Optional ByVal MDIChild As Boolean)
    Dim hSysMenu As Long
    Dim nCnt As Long
    Dim cID As Long
    hSysMenu = GetSystemMenu(hwnd, False)
    If hSysMenu = 0 Then Exit Function
    nCnt = GetMenuItemCount(hSysMenu)
    If MDIChild Then
        cID = 3
    Else
        cID = 1
    End If
    If nCnt Then
        DisableClose = RemoveMenu(hSysMenu, nCnt - cID, MF_BYPOSITION Or MF_REMOVE)
        DisableClose = RemoveMenu(hSysMenu, nCnt - cID - 1, MF_BYPOSITION Or MF_REMOVE)
        nCnt = GetMenuItemCount(hSysMenu)
        DisableClose = DeleteMenu(hSysMenu, nCnt - 1, MF_BYPOSITION)
        nCnt = GetMenuItemCount(hSysMenu)
        DisableClose = DeleteMenu(hSysMenu, nCnt - 1, MF_BYPOSITION)
    End If
End Function