//初始化时将具体的聚集对象传入
public ConcreteIteratorDesc(ConcreteAggregate aggregate)
{
this.aggregate = aggregate;
current = aggregate.Count - 1;
}
//初始化时将具体的聚集对象传入
public ConcreteIterator(ConcreteAggregate aggregate)
{
this.aggregate = aggregate;
}
