C#基础概念二十五问

 1using System;
 2using System.Collections.Generic;
 3using System.Text;
 4 
 5namespace Example04
 6{
 7    基类，抽象类#region 基类，抽象类
 8    public abstract class BaseClass
 9    {
10        //抽象属性，同时具有get和set访问器表示继承类必须将该属性实现为可读写
11        public abstract String Attribute
12        {
13            get;
14            set;
15        }
16 
17        //抽象方法，传入一个字符串参数无返回值
18        public abstract void Function(String value);
19 
20        //抽象事件，类型为系统预定义的代理(delegate)：EventHandler
21        public abstract event EventHandler Event;
22 
23        //抽象索引指示器，只具有get访问器表示继承类必须将该索引指示器实现为只读
24        public abstract Char this[int Index]
25        {
26            get;
27        }
28    }
29    #endregion
30 
31    继承类#region 继承类
32    public class DeriveClass : BaseClass
33    {
34        private String attribute;
35 
36        public override String Attribute
37        {
38            get
39            {
40                return attribute;
41            }
42            set
43            {
44                attribute = value;
45            }
46        }
47        public override void Function(String value)
48        {
49            attribute = value;
50            if (Event != null)
51            {
52                Event(this, new EventArgs());
53            }
54        }
55        public override event EventHandler Event;
56        public override Char this[int Index]
57        {
58            get
59            {
60                return attribute[Index];
61            }
62        }
63    }
64    #endregion
65 
66    class Program
67    {
68        static void OnFunction(object sender, EventArgs e)
69        {
70            for (int i = 0; i < ((DeriveClass)sender).Attribute.Length; i++)
71            {
72                Console.WriteLine(((DeriveClass)sender)[i]);
73            }
74        }
75        static void Main(string[] args)
76        {
77            DeriveClass tmpObj = new DeriveClass();
78 
79            tmpObj.Attribute = "1234567";
80            Console.WriteLine(tmpObj.Attribute);
81 
82            //将静态函数OnFunction与tmpObj对象的Event事件进行关联
83            tmpObj.Event += new EventHandler(OnFunction);
84 
85            tmpObj.Function("7654321");
86 
87            Console.ReadLine();
88        }
89    }
90}

 1using System;
 2using System.Collections.Generic;
 3using System.Text;
 4 
 5namespace Example05Lib
 6{
 7    public class Class1
 8    {
 9        internal String strInternal = null;
10        public String strPublic;
11        internal protected String strInternalProtected = null;
12    }
13}