static void Main(string[] args)
{
MSExcel excel = new MSExcel();
excel.New();
excel.Close();
//-----------------------------------
IMsProduct msExcel = new MSExcel();
msExcel.New();
//Type Casting
}
static void Main(string[] args)
{
//Interface MSOffice
MSOffice office = new MSExcel();
//Interface MSProduct
MSProduct product = new MSExcel();
MSExcel excel = new MSExcel();
excel.Print();
office.NewFile();
excel.NavigationBar();
MSProduct msProduct = (MSProduct)office;
msProduct.NavigationBar();
((MSProduct)office).NavigationBar();
product.NavigationBar();
}