C#中的迭代器
作者:互联网
原文链接:http://www.cnblogs.com/Celvin-Xu/p/3434285.html
迭代器:迭代集合中的每一项,无需关心集合中的内容。
实现迭代器的传统方式是使用迭代器模式,迭代器模式的示意图如下:
具体代码如下:
class Person { public string Name { get; set; } public int Age { get; set; } public Person(string name, int age) { this.Name = name; this.Age = age; } } class People:IEnumerable { public Person[] pvalue; public People(Person[] p) { pvalue = p; } public IEnumerator GetEnumerator() { return new PeopleEnumerator(this); } }
class PeopleEnumerator:IEnumerator { Person[] pvalue; int position; public PeopleEnumerator(People p) { this.pvalue = p.pvalue; position = -1; } public bool MoveNext() { if (position >= -1 && position < pvalue.Length) { position++; } return position < pvalue.Length; } public object Current { get { if (position >= 0 && position < pvalue.Length) { return pvalue[position]; } else { return null; } } } public void Reset() { position = -1; } }
class Program { static void Main(string[] args) { Person[] PClassOne = new Person[4]; PClassOne[0] = new Person("夏利", 22); PClassOne[1] = new Person("大众", 25); PClassOne[2] = new Person("华为", 23); PClassOne[3] = new Person("中兴", 24); Console.WriteLine("传统的迭代器模式"); People Ppeople = new People(PClassOne); IEnumerator PE = Ppeople.GetEnumerator(); while (PE.MoveNext()) { Person p = (Person)PE.Current; Console.WriteLine("我的名字叫{0},我的年龄为{1}", p.Name, p.Age); } Console.ReadKey(); } }
输出为:
.net 可以使用yield 的方式简化迭代器的使用,将People改成如下的形式
class People:IEnumerable { public Person[] pvalue; public People(Person[] p) { pvalue = p; } public IEnumerator GetEnumerator() { for (int i = 0; i < pvalue.Length; i++) { yield return pvalue[i]; } } }
无需在手动写IEnumerator,即可行程一个有效的迭代器。
转载于:https://www.cnblogs.com/Celvin-Xu/p/3434285.html
标签:迭代,People,C#,pvalue,Person,position,public 来源: https://blog.csdn.net/weixin_30455067/article/details/97912290