BlogEngine学习一：操作符重载

时间：2011-01-07 来源：程序诗人

　　先来看看在BlogEngine系统中，操作符的重载方式如下：

/// <summary>
 /// Checks to see if two business objects are the same.
 /// </summary>
 public static bool operator ==(BusinessBase<TYPE, KEY> first, BusinessBase<TYPE, KEY> second)
 {
 if (Object.ReferenceEquals(first, second))
 {
 return true;
 }
 if ((object)first == null || (object)second == null)
 {
 return false;
 }
 return first.GetHashCode() == second.GetHashCode();
 }

 /// <summary>
 /// Checks to see if two business objects are different.
 /// </summary>
 public static bool operator !=(BusinessBase<TYPE, KEY> first, BusinessBase<TYPE, KEY> second)
 {
 return !(first == second);
 }

　　下面的列表将向你展示在C#语言中，可以进行重载的操作符：

+, -, *, /, %, &, |, <<, >> 所有的C#字节操作符都能够被重载。

　　+, -, !, ~, ++, –, true, false 所有的C#一元操作符都能够被重载。

==, !=, <, >, <= , >= 所有的C#二元操作符都能够被重载。

　　&&, || ,=, . , ?:, ->, new, is, as, size of 这些操作符都不能够被重载.

　　下面就以代码来说明操作符重载的方法:

类TestOperator如下:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

/// <summary>
///TestOperator 的摘要说明
/// </summary>
public class TestOperator
{
 public int Life; //生命

 public TestOperator(int life)
 {
 this.Life = life;
 }

 public static TestOperator operator +(TestOperator role1,TestOperator role2)
 {
 return new TestOperator(role1.Life+role2.Life);
 }

 public static TestOperator operator +(int _life, TestOperator role2)
 {
 return new TestOperator(_life) + role2;
 }

 public static TestOperator operator +(TestOperator role1, int _life)
 {
 return role1 + new TestOperator(_life);
 }
}

然后在前台页面上的使用方式如下:

using System;

public partial class _Default : System.Web.UI.Page
{
 protected void Page_Load(object sender, EventArgs e)
 {
 Response.Write("操作符重载: ");
 TestOperator life1 = new TestOperator(100);
 TestOperator life2 = new TestOperator(200);
 TestOperator _result1 = life1 + life2;
 Response.Write(_result1.Life);
 Response.Write(" ----------------------- ");
 TestOperator life11 = new TestOperator(100);
 int life22 = 120;
 TestOperator _result2 = life11 + life22;
 Response.Write(_result2.Life);
 Response.Write(" ----------------------- ");
 int life111 = 100;
 TestOperator life222 = new TestOperator(100);
 TestOperator _result3 = life111 + life222;
 Response.Write(_result3.Life);
 }
}

然后得到的结果如下:

操作符重载:
300
-----------------------
220
-----------------------
200

这样,就简单的实现了操作符的重载,需要说明的是,在实际项目中,操作符的重载可能比这个复杂的多,只要正确的处理就行了.