1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6
7 using System.Collections;
8
9 namespace day01
10 {
11 class Class28
12 {
13 static void Main(string[] args)
14 {
15 foreach(string temp in SimpleList())
16 {
17 Console.WriteLine(temp);
18 }
19 Console.ReadKey();
20 }
21 static IEnumerable SimpleList()
22 {
23 yield return "string 1";
24 yield return "string 2";
25 yield return "string 3";
26 }
27 }
28 }
代码二
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6
7 using System.Collections;
8
9 namespace day01
10 {
11 class Class29
12 {
13 static void Main(string[] args)
14 {
15 Cat catDictionary = new Cat();
16 catDictionary.Add("1001", new Cat("zhangsan"));
17 catDictionary.Add("1002", new Cat("lisi"));
18 catDictionary.Add("1031", new Cat("wangwu"));
19
20 foreach(Animal temp in catDictionary)
21 {
22 Console.WriteLine("{0} {1}", temp.ToString(), temp.Name);
23 }
24 Console.ReadKey();
25 }
26 }
27 public abstract class Animal : DictionaryBase
28 {
29 protected string name;
30 public string Name { get; set; }
31 public Animal()
32 {
33 Name = "default";
34 }
35 public Animal(string name)
36 {
37 Name = name;
38 }
39 public abstract void Run();
40 public abstract void Sleep();
41 public override string ToString()
42 {
43 return "name: " + Name;
44 }
45 public void Add(string newId, Animal animal)
46 {
47 Dictionary.Add(newId, animal);
48 }
49 public void Remove(string newId)
50 {
51 Dictionary.Remove(newId);
52 }
53 public Animal this[string newId]
54 {
55 get
56 {
57 return (Animal)Dictionary[newId];
58 }
59 set
60 {
61 Dictionary[newId] = value;
62 }
63 }
64 //添加迭代器
65 public new IEnumerator GetEnumerator()
66 {
67 foreach(object temp in Dictionary.Values)
68 {
69 yield return (Animal)temp;
70 }
71 }
72 }
73 public class Cat : Animal
74 {
75 //这个构造器该怎么理解？
76 public Cat()
77 {
78
79 }
80 public Cat(string name) : base(name)
81 {
82
83 }
84 public override void Run()
85 {
86 Console.WriteLine("animal name: {0} is running", Name);
87 }
88
89 public override void Sleep()
90 {
91 Console.WriteLine("animal name: {0} is sleeping", Name);
92 }
93 }
94 }
