using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsIEnumerator
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        //创建迭代器，需要实现IEnumerable接口
        public class Family : System.Collections.IEnumerable
        {
            string[] MyFamily = { "父亲", "母亲", "弟弟", "妹妹" };
            public System.Collections.IEnumerator GetEnumerator()
            {
                //使用for依次返回数组或集合中的每一个元素
                for (int i = 0; i < MyFamily.Length; i++)
                {
                    yield return MyFamily[i];
                }
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            //实例化迭代器
            Family myfamily = new Family();
            //遍历迭代器，相当于调用GetEnumerator()方法
            foreach (string str in myfamily)
            {
                richTextBox1.Text += str + "\n";
            }
        }
    }
}