[C#]实现IEnumerable接口来使用foreach语句的一个实例

[C#]实现IEnumerable接口来使用foreach语句的一个实例 - 李浩的博客园...
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            using System; 
        
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            using System.Collections.Generic; 
        
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            using System.Linq; 
        
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            using System.Text; 
        
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            using System.Collections; 
        
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            namespace IEnumeratorSample 
        
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            { 
        
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                class Person : IEnumerable                         //派生自IEnumerable,同样定义一个Personl类 
        
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                { 
        
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                    public string Name; 
        
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                    public string Age; 
        
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                    public Person(string name, string age) 
        
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                    { 
        
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                        Name = name; 
        
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                        Age = age; 
        
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                    } 
        
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                    private Person[] per; 
        
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                    public Person(Person[] array)//重载构造函数，迭代对象，用一个数组来存放Person的集合，在后面用foreach来访问，但是仍然要实现GetEnumerator() 
        
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                    { 
        
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                        per = new Person[array.Length]; 
        
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                        for (int i = 0; i < array.Length; i++) 
        
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                        { 
        
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                            per[i] = array[i]; 
        
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                        } 
        
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                    } 
        
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                    public IEnumerator GetEnumerator()//实现GetEnumerator()接口 
        
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                    { 
        
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                        return new PersonEnum(per);//在这里调用PersonEnum 
        
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                    } 
        
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                } 
        
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                class PersonEnum : IEnumerator                    //实现foreach语句内部,并派生 
        
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                { 
        
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                    public Person[] _per; 
        
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                    int position = -1; 
        
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                    public PersonEnum(Person[] list) 
        
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                    { 
        
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                        _per = list; 
        
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                    } 
        
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                    public bool MoveNext() 
        
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                    { 
        
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                        position++; 
        
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                        return (position < _per.Length); 
        
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                    } 
        
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                    public void Reset() 
        
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                    { 
        
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                        position = -1; 
        
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                    } 
        
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                    public object Current 
        
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                    { 
        
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                        get
        
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                        { 
        
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                            try
        
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                            { 
        
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                                return _per[position]; 
        
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                            } 
        
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                            catch (IndexOutOfRangeException) 
        
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                            { 
        
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                                throw new InvalidOperationException(); 
        
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                            } 
        
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                        } 
        
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                    } 
        
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                } 
        
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                class Program 
        
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                { 
        
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                    static void Main(string[] args) 
        
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                    { 
        
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                        Person[] per = new Person[2]                //同样初始化并定义2个Person对象 
        
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                        { 
        
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                            new Person("guojing","21"), 
        
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                            new Person("muqing","21"), 
        
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                        }; 
        
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                        Person personlist = new Person(per);            //初始化对象集合 
        
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                        foreach (Person p in personlist)                //使用foreach语句 
        
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                            Console.WriteLine("Name is " + p.Name + " and Age is " + p.Age); 
        
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                        Console.ReadKey(); 
        
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                    } 
        
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                } 
        
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            }