static void Main(string[] args)
{
var user = new PhoneUser(new EricssonPhone()); //引用接口，耦合变得很松
// var user = new PhoneUser(new NokiaPhone());
user.UsePhone();
Console.WriteLine("Hello World!");
}
static void Main(string[] args)
{
var user = new PhoneUser(new NokiaPhone());
//引入接口后，会变成松耦合
//var user = new PhoneUser(new EricssonPhone());
user.UsePhone();
Console.ReadKey();
}
