C# - 接口的继承

代码：

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;

 namespace 接口
 {
     /// <summary>
     /// 接口：定义一个统一的标准
     /// 声明接口，接口中，只包含成员的生命，不包含任何的代码实现。
     /// 接口成员总是公有的，不添加也不需要添加public，也不能声明虚方法和虚静态方法
     /// </summary>
     interface IBankAccount
     {
         //方法
         void PayIn(decimal amount);

         //方法
         bool WithShowMyself(decimal amount);

         //属性
         decimal Balance { get; }
     }

     /// <summary>
     /// 继承自IBankAccount的接口
     /// </summary>
     interface ITransferBankAccount : IBankAccount
     {
         //转账          ：转入的目的地             ：转入金额
         bool TransferTo(IBankAccount destination, decimal amount);
     }

     class SaveAcount : IBankAccount
     {
         //私有变量
         private decimal banlance;

         //存款
         public void PayIn(decimal amount)
         {
             banlance += amount;
         }

         //取款
         public bool WithShowMyself(decimal amount)
         {
             if (banlance >= amount)
             {
                 banlance -= amount;
                 return true;
             }
             else
             {
                 Console.WriteLine("余额不足！");
                 return false;
             }
         }

         //账户余额
         public decimal Balance
         {
             get
             {
                 return banlance;
             }
         }
     }

     //实现接口的类的相应成员必须添加public修饰
     class ITransferAccount : ITransferBankAccount
     {
         //私有变量
         private decimal banlance;

         //存款
         public void PayIn(decimal amount)
         {
             banlance += amount;
         }

         //取款
         public bool WithShowMyself(decimal amount)
         {
             if (banlance >= amount)
             {
                 banlance -= amount;
                 return true;
             }
             else
             {
                 Console.WriteLine("余额不足！");
                 return false;
             }
         }

         //账户余额
         public decimal Balance
         {
             get
             {
                 return banlance;
             }
         }

         //转账
         public bool TransferTo(IBankAccount destination, decimal amount)
         {
             bool result = WithShowMyself(amount);

             if (result == true)
             {
                 destination.PayIn(amount);
             }

             return result;
         }
     }

     class Program
     {
         static void Main(string[] args)
         {
             IBankAccount MyAccount = new SaveAcount();

             ITransferAccount YourAccount = new ITransferAccount();

             MyAccount.PayIn();

             YourAccount.PayIn();

             YourAccount.TransferTo(MyAccount, );

             Console.WriteLine(MyAccount.Balance);//
             Console.WriteLine();
             Console.WriteLine(YourAccount.Balance);//

             Console.ReadKey();
         }
     }
 }