如何实现属性，如同组数一样通过index读写？

Question

本帖最后由 pfworld 于 2009-06-07 12:31:07 编辑

Answer 1

  public class Topic
        {
            private string title01;            public string Title01
            {
                get { return title01; }
                set { title01 = value; }
            }            private string title02;            public string Title02
            {
                get { return title02; }
                set { title02 = value; }
            }            private string title03;            public string Title03
            {
                get { return title03; }
                set { title03 = value; }
            }            public string this[int index]
            {
                get
                {
                    switch (index)
                    {
                        case 0:
                            return title01;
                        case 1:
                            return title02;
                        case 2:
                            return title03;
                        default:
                            return "";
                    }
                }
                set
                {
                    switch (index)
                    {
                        case 0:
                            title01 = value;
                            return;
                        case 1:
                            title02 = value;
                            return;
                        case 2:
                            title03 = value;
                            return;
                        default:
                            return;
                    }
                           
                }
            }
        } 
这样写 增加索引属性.

Answer 2

谢谢！！想起来了！！this索引器！！晕！！

Answer 3

对，用this撒，返回不同的类型，试试泛型

Answer 4

也可以返回object，在强制类型转换

Answer 5

public object this[int index] 
            { 
                get 
                { 
                    switch (index) 
                    { 
                        case 0: 
                            return title01; 
                        case 1: 
                            return title02; 
                        case 2: 
                            return title03; 
                        default: 
                            return ""; 
                    } 
                } 
                set 
                { 
                    switch (index) 
                    { 
                        case 0: 
                            title01 = value; 
                            return; 
                        case 1: 
                            title02 = value; 
                            return; 
                        case 2: 
                            title03 = value; 
                            return; 
                        default: 
                            return; 
                    } 
                          
                } 但是这个要进行数据转换！！有好的方法不？

Answer 6

使用 this 索引器。无法返回不同类型的值，有一个替代的方法是，返回 object 类型，引用类型没问题，值类型的话返回前boxing一下。然后在外部去unboxing 或者使用 as 操作符来还原类型。或者，你可以使用索引器重载public int this[int index]
{
}public string this[string index]
{
}....

Answer 7

我现在要返回三种类型  string.double,bool  关键是索引器的参数不要确定，一般int，string，不知道还有什么号方法！！或者this.（int index,string index2,string index3）使用this[1,null,null]??