C#中奇妙的操作符重載
2024-07-21 02:19:31
供稿：網(wǎng)友
c#中奇妙的操作符重載
細(xì)心的朋友可能發(fā)現(xiàn)，c#雖然可以重載操作符，但和c++比較起來，卻有很大的不同。定義的時候重載操作符方法必須是static，而且至少有一個參數(shù)（一目和二目分別是一個和兩個），c#和c++比起來，最重要的特征是：<、>；==、!=；true、false必須成對出現(xiàn)，即重載了“<”就必須重載“>”，重載了“==”就必須重載“！=”，重載了“true”就必須重載“false”；另外，還必須實現(xiàn)基類object的兩個虛方法：gethashcode()和equals(object obj)。
以下是程序代碼，有些地方寫得不完善，只能說僅僅說明了問題，不對之處請指教：
using system;
using system.xml;
namespace consoleapplication8
{
/// <summary>
/// 姓名類
/// </summary>
class namer
{
private string firstname;
private string lastname;
public namer()
{
this.init(null,null);
}
public namer(string fn,string ln)
{
this.init(fn,ln);
}
private void init(string fn,string ln)
{
this.firstname=fn;
this.lastname=ln;
}
/// <summary>
/// 重載運算符true
/// </summary>
/// <param name="n"></param>
/// <returns>如果姓名中姓或名有一個為空，就返回假</returns>
public static bool operator true(namer n)
{
if(n.firstname==null || n.lastname==null)
return false;
else
return true;
}
/// <summary>
/// 重載運算符false
/// </summary>
/// <param name="n"></param>
/// <returns></returns>
public static bool operator false(namer n)
{
if(n.firstname==null || n.lastname==null)
return false;
else
return true;
}
/// <summary>
/// 重載運算符==
/// </summary>
/// <param name="n1"></param>
/// <param name="n2"></param>
/// <returns></returns>
public static bool operator ==(namer n1,namer n2)
{
if(n1.firstname==n2.firstname && n1.lastname==n2.lastname)
return true;
else
return false;
}
/// <summary>
/// 重載運算符！=
/// </summary>
/// <param name="n1"></param>
/// <param name="n2"></param>
/// <returns></returns>
public static bool operator !=(namer n1,namer n2)
{
if(n1.firstname!=n2.firstname || n1.lastname !=n2.lastname)
return true;
else
return false;
}
/// <summary>
/// 重載運算符>
/// </summary>
/// <param name="n1"></param>
/// <param name="n2"></param>
/// <returns></returns>
public static bool operator >(namer n1,namer n2)
{
return (n1.firstname.compareto(n2.firstname)>0 && n1.lastname.compareto(n2.lastname)>0);
}
/// <summary>
/// 重載運算符<
/// </summary>
/// <param name="n1"></param>
/// <param name="n2"></param>
/// <returns></returns>
public static bool operator <(namer n1,namer n2)
{
return (n1.firstname.compareto(n2.firstname)<0 && n1.lastname.compareto(n2.lastname)<0);
}
/// <summary>
/// 重寫方法，必須有,后面的111是亂加的，你也可以寫其它的
/// </summary>
/// <returns></returns>
public override int gethashcode()
{
return base.gethashcode()*111;
}
/// <summary>
/// 重寫方法，必須有
/// </summary>
/// <param name="obj"></param>
/// <returns></returns>
public override bool equals(object obj)
{
return base.equals (obj);
}
/// <summary>
/// 重寫方法，必須有
/// </summary>
/// <returns></returns>
public override string tostring()
{
return "姓:"+this.firstname+" 名:"+this.lastname;
}
public static void main()
{
namer n1=new namer("li","zanhong");
namer n2=new namer("ahang","aan");
//namer n2=new namer("li","zanhong");
if(n1==n2)
console.writeline("一樣的名字");
else
console.writeline("不一樣的名字");
/////////////////////////////////////
if(n1!=n2)
console.writeline("不一樣的名字成立");
else
console.writeline("同樣的名字成立");
/////////////////////////////////////
if(n1>n2)
console.writeline(n1.tostring()+">"+n2.tostring());
else if(n1<n2)
console.writeline(n1.tostring()+"<"+n2.tostring());
else
console.writeline("沒有正確比較");
console.readline();
}
}
}
