重载操作符

影者东升

重 载 操 作 符 重载操作符 重载操作符

1.索引器
索引器语法一般用于容器类的API，没有特别的好处，就是形式上简洁一些。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace CSharp基础语法
{
  class MyArray
  {
    private int[] items;
    public MyArray(int capacity)
    {
      items = new int[capacity];
    }
    public void SetItem(int i ,int val)
    {
      items[i] = val;
    }
    public int GetItem(int i)
    {
      return items[i];
    }
    // 索引器
    public int this[int index]
    {
      get
      {
        return items[index];
      }
      set
      {
        items[index] = value;
      }
    }
    public int Size()
    {
      return this.items.Length;
    }
  }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace CSharp基础语法
{
  class Program
  {
    static void Main(string[] args)
    {
      MyArray a = new MyArray(4);
      a[0] = 12;
      a[1] = 12;
      a[2] = 12;
      a[3] = 12;
      for(int i = 0; i < a.Size(); i++)
      {
        Console.WriteLine(a[i] + "  ");
      }
      a.SetItem(0, 16);
      a.SetItem(0, 16);
      a.SetItem(0, 16);
      a.SetItem(0, 16);
      for (int i = 0; i < a.Size(); i++)
      {
        Console.WriteLine(a.GetItem(i) + "  ");
      }
      Console.WriteLine("\n");
    }
  }
}

2.重载操作符

MyFraction f1 =new MyFraction(1, 3);
MyFraction f2 = new MyFraction(2, 5);
MyFraction result = f1 *f2;
Console.WriteLine("结果: "+result);

MyFraction是一个类，也能支持乘法运算
在C#里面，可以重载操作符，

public static MyFraction operator *(MyFraction a, MyFraction b){
MyFraction result = new MyFraction();
result.num = a.num " b.num;
result.den = a.den * b.den;
return result;
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace CSharp基础语法
{
  class MyFraction
  {
    public int num = 0;
    public int den = 1;
    public MyFraction() { }
    public MyFraction(int num ,int den)
    {
      this.num = num;
      this.den = den;
    }
    public override string ToString()
    {
      return num + "/" + den;
    }
    // 重载乘法操作符
    public static MyFraction operator *(MyFraction a,MyFraction b)
    {
      MyFraction res = new MyFraction();
      res.num = a.num * b.num;
      res.den = a.den * b.den;
      return res;
    }
    // 普通写法
    public static MyFraction  Multiply(MyFraction a, MyFraction b)
    {
      MyFraction res = new MyFraction();
      res.num = a.num * b.num;
      res.den = a.den * b.den;
      return res;
    }
  }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace CSharp基础语法
{
  class Program
  {
    static void Main(string[] args)
    {
      // 定义两个分数 1/3 和 2/5
      MyFraction f1 = new MyFraction(1, 3);
      MyFraction f2 = new MyFraction(2, 5);
      // 相乘
      MyFraction res = f1 * f2;
      Console.WriteLine("结果： " + res);
    }
  }
}