public Flyweight GetFlyweight(string key)
{
if (!(flyweights[key] is Flyweight flyweight))
{
Console.WriteLine("驻留池中不存在字符串" + key);
flyweight = new ConcreteFlyweight(key);
}
return(flyweight);
//return flyweights[key] as Flyweight;
}
static void Main(string[] args)
{
//定义外部状态，例如字母的位置等信息
int externalstate = 10;
//初始化享元工厂
FlyweightFactory factory = new FlyweightFactory();
//判断是否已经创建了字母A，如果已经创建就直接使用创建的对象A
Flyweight fa = factory.GetFlyweight("A");
if (fa != null)
{
fa.Operation(--externalstate);
}
//判断是否已经创建了字母B
Flyweight fb = factory.GetFlyweight("B");
if (fb != null)
{
fb.Operation(--externalstate);
}
//判断是否已经创建了字母C
Flyweight fc = factory.GetFlyweight("C");
if (fc != null)
{
fc.Operation(--externalstate);
}
//判断是否已经创建了字母D
Flyweight fd = factory.GetFlyweight("D");
if (fd != null)
{
fd.Operation(--externalstate);
}
else
{
Console.WriteLine("驻留池中不存在字符串D");
ConcreteFlyweight d = new ConcreteFlyweight("D");
factory.flyweights.Add("D", d);
}
Console.ReadLine();
}