接口里不能包括字段，构造函数，析构函数，静态成员或常量等，否则会导致错误

2019-11-14 13:48:11

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定义一个借口，接口封装了矩形的长和宽，而且还包含一个自定义的方法以计算矩形的面积。然后定义一个类，继承自该接口，在该类中实现接口中自定义方法。

 1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Text; 5  6 namespace Test06 7 { 8     interface ImyInterface 9     {10         /// <summary>11         /// 长12         /// </summary>13         int Width14         {15             get;16             set;17         }18         /// <summary>19         /// 宽20         /// </summary>21         int Height22         {23             get;24             set;25         }26         /// <summary>27         /// 计算矩形面积28         /// </summary>29         int Area();////////  int Area(int Width, int Height);  30     }31     class PRogram : ImyInterface//继承自接口32     {33         private int width = 0;34         private int height = 0;35         /// <summary>36         /// 长37         /// </summary>38         public int Width39         {40             get41             {42                 return width;43             }44             set45             {46                 width = value;47             }48         }49         /// <summary>50         /// 宽51         /// </summary>52         public int Height53         {54             get55             {56                 return height;57             }58             set59             {60                 height = value;61             }62         }63         /// <summary>64         /// 计算矩形面积65         /// </summary>66         public int Area(int Width,int Height)67         {68             return Width * Height;69         }70         static void Main(string[] args)71         {72             Program program = new Program();//实例化Program类对象73             ImyInterface imyinterface = program;//使用派生类对象实例化接口ImyInterface74             imyinterface.Width = 5;//为派生类中的Width属性赋值75             imyinterface.Height = 3;//为派生类中的Height属性赋值76             Console.WriteLine("矩形的面积为：" + imyinterface.Area(3,5));77         }78     }79 }

下面是正确的：

 1 using System; 2 using System.Collections.Generic; 3 using System.Linq; 4 using System.Text; 5  6 namespace Test06 7 { 8     interface ImyInterface 9     {10         /// <summary>11         /// 长12         /// </summary>13         int Width14         {15             get;16             set;17         }18         /// <summary>19         /// 宽20         /// </summary>21         int Height22         {23             get;24             set;25         }26         /// <summary>27         /// 计算矩形面积28         /// </summary>29         int Area();30     }31     class Program : ImyInterface//继承自接口32     {33         int width = 0;34         int height = 0;35         /// <summary>36         /// 长37         /// </summary>38         public int Width39         {40             get41             {42                 return width;43             }44             set45             {46                 width = value;47             }48         }49         /// <summary>50         /// 宽51         /// </summary>52         public int Height53         {54             get55             {56                 return height;57             }58             set59             {60                 height = value;61             }62         }63         /// <summary>64         /// 计算矩形面积65         /// </summary>66         public int Area()67         {68             return Width * Height;69         }70         static void Main(string[] args)71         {72             Program program = new Program();//实例化Program类对象73             ImyInterface imyinterface = program;//使用派生类对象实例化接口ImyInterface74             imyinterface.Width = 5;//为派生类中的Width属性赋值75             imyinterface.Height = 3;//为派生类中的Height属性赋值76             Console.WriteLine("矩形的面积为：" + imyinterface.Area());77         }78     }79 }