// 建構子注入
public Socket(IElectricalPlug plug)
{
if (plug == null)
{
throw new ArgumentNullException("plug 為空值");
}
this._plug = plug;
}
// 裝飾者模式, 用建構子注入要被裝飾的插頭
public SecureHairDryerPlug(IElectricalPlug plug, string identity)
{
this.plug = plug;
this.identity = identity;
}
