C++运算符重载学习总结

柔情只为你懂 2021-11-17 15:40 277阅读 0赞

在C ++中，我们可以使运算符适用于用户定义的类。 这意味着C ++能够为运算符提供数据类型的特殊含义，这种能力称为运算符重载。

例如，我们可以在像String这样的类中重载运算符'+'，这样我们就可以通过使用+来连接两个字符串。

其它示例中算术运算符可以重载的的类是复数，小数，大整数等。

运算符重载的语法格式：

Return\_Type classname :: operator op(Argument list)

Function Body

在上面的语法中，Return\_Type是要返回给另一个对象的值类型，operator op是运算符是关键字的函数，op是要重载的运算符。

运算符函数必须是非静态（成员函数）或友元函数。

运算符重载可以通过三种方法完成，它们是

1) 重载一元运算符。

2) 重载二元运算符。

3) 使用友元函数重载二元运算符。

以下是定义运算符函数的一些条件/规则：

l 在非静态函数的情况下，二元运算符应该只有一个参数，而一元不应该有一个参数。

l 在友元函数的情况下，二元运算符应该只有两个参数，而一元应该只有一个参数。

l 如果实现了运算符重载，则所有类成员对象都应该是公共的。

运算符函数和普通函数有什么区别？

运算符函数与普通函数相同。 唯一的区别是，运算符函数的名称始终是operator关键字，后跟运算符符号，并且在使用相应的运算符时调用运算符函数。

除了极个别的运算符外，大部分运算符都可以被重载。

以下是可以重载的运算符列表：

![1012444-20190628140308422-348786570.png][]

以下是不可以重载的运算符列表：

![1012444-20190628140322836-1002021228.png][]

为什么（点），::，？：和sizeof不可以重载看[这里][Link 1]解释。

关于运算符重载的重要方面：

1）为了使操作符重载起作用，其中一个操作数必须是用户定义的类对象。

2）赋值运算符：编译器自动为每个类创建一个默认赋值运算符。 默认赋值运算符确实将右侧的所有成员分配到左侧，并且在大多数情况下都能正常工作（此行为与复制构造函数相同）。

3）转换运算符：我们还可以编写可用于将一种类型转换为另一种类型的转换运算符。重载的转换运算符必须是成员方法。 其他运算符可以是成员方法或全局方法。

4）任何可以用单个参数调用的构造函数都可以用作转换构造函数，这意味着它也可以用于隐式转换为正在构造的类。

综合例子：学习测试，仅供参考！

OperatorOverloadingClass.h

<table style="font-family:Consolas, 'Courier New';font-size:12px;vertical-align:text-top;line-height:15px;"> 
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 </div> </td> 
 <td>&nbsp;</td> 
 <td style="vertical-align:text-top;color:#000000;"> 
 <div> 
 #ifndef 
 &nbsp;OPERATOROVERLOADINGCLASS_H 
 #define 
 &nbsp;OPERATOROVERLOADINGCLASS_H 
 #include 
 &nbsp;&lt;iostream&gt; 
 using 
 &nbsp; 
 namespace 
 &nbsp;std; 
 const 
 &nbsp; 
 int 
 &nbsp;SIZE&nbsp;=&nbsp; 
 10 
 ; 
 class 
 &nbsp;OperatorOverloadingClass { 
 public 
 : &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass(); &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass( 
 const 
 &nbsp; 
 int 
 &nbsp;&amp;number, &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 const 
 &nbsp; 
 float 
 &nbsp;&amp;fnumber); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;赋值运算符 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 void 
 &nbsp; 
 operator 
 &nbsp;=&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;m_number&nbsp;=&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;函数调用()运算符 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 ()( 
 int 
 &nbsp;a,&nbsp; 
 int 
 &nbsp;b,&nbsp; 
 int 
 &nbsp;c) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;D; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;just&nbsp;put&nbsp;random&nbsp;calculation 
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;D.m_number&nbsp;=&nbsp;a&nbsp;+&nbsp;b&nbsp;+&nbsp;c; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;D; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 void 
 &nbsp;print(); &nbsp;&nbsp;&nbsp;&nbsp; 
 /*&nbsp;OperatorOverloading &nbsp;&nbsp;&nbsp;&nbsp;*/ 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;算术运算符 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;+ 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;+&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;- 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;-&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;* 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;*&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;/ 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;/&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;% 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;%&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;关系运算符 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&lt; 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;&lt;&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&gt; 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;&gt;&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&lt;= 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;&lt;=&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&gt;= 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;&gt;=&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;== 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;==&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;!= 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;!=&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;位运算符 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;^ 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;^&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&amp; 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;&amp;&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;| 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;|&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;逻辑运算符 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&amp;&amp; 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;&amp;&amp;&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;|| 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 bool 
 &nbsp; 
 operator 
 &nbsp;||&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;取地址运算符&amp; 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 int 
 &nbsp;* 
 operator 
 &nbsp;&amp;() &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;&amp; 
 this 
 -&gt;m_number; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;内存操作运算符* 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 int 
 &nbsp; 
 operator 
 &nbsp;*(OperatorOverloadingClass&nbsp;*obj) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;obj-&gt;m_number; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;输入输出运算符 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&lt;&lt; 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 friend 
 &nbsp;ostream&nbsp;&amp; 
 operator 
 &lt;&lt;(ostream&nbsp;&amp;output,&nbsp; 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj&nbsp;) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;output&nbsp;&lt;&lt;&nbsp; 
 "number&nbsp;:&nbsp;" 
 &nbsp;&lt;&lt;&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;output; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;&gt;&gt; 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 friend 
 &nbsp;istream&nbsp;&amp; 
 operator 
 &gt;&gt;(istream&nbsp;&amp;input,&nbsp;OperatorOverloadingClass&nbsp;&amp;obj) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;input&nbsp;&gt;&gt;&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;input; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;自增自减运算符 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;++i 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;++(); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;i++ 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;++( 
 int 
 ); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;--i 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;--(); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;i-- 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp; 
 operator 
 &nbsp;--( 
 int 
 ); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;数组成员访问运算符[] 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 int 
 &nbsp;&amp; 
 operator 
 []( 
 int 
 &nbsp;i) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 if 
 (&nbsp;i&nbsp;&gt;&nbsp;SIZE&nbsp;) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;cout&nbsp;&lt;&lt;&nbsp; 
 "Index&nbsp;out&nbsp;of&nbsp;bounds" 
 &nbsp;&lt;&lt;&nbsp;endl; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;return&nbsp;first&nbsp;element. 
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;arr[ 
 0 
 ]; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;arr[i]; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;类成员访问运算符-&gt; 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;https://www.cnblogs.com/codingmengmeng/p/9064702.html 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;复合赋值运算符：+=、-=、*=、/=、%=、&lt;&lt;=、&gt;&gt;=、^=、&amp;=、|= 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 void 
 &nbsp; 
 operator 
 &nbsp;+=&nbsp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;m_number&nbsp;+=&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;其余类似 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;重载类型转换 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 operator 
 &nbsp; 
 int 
 () &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;m_number; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 operator 
 &nbsp; 
 float 
 () &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;m_fnumber; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;new&nbsp;delete 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 void 
 &nbsp;* 
 operator 
 &nbsp; 
 new 
 (size_t&nbsp;size); &nbsp;&nbsp;&nbsp;&nbsp; 
 void 
 &nbsp; 
 operator 
 &nbsp; 
 delete 
 ( 
 void 
 &nbsp;*p); &nbsp;&nbsp;&nbsp;&nbsp; 
 void 
 &nbsp;* 
 operator 
 &nbsp; 
 new 
 [](size_t&nbsp;size); &nbsp;&nbsp;&nbsp;&nbsp; 
 void 
 &nbsp; 
 operator 
 &nbsp; 
 delete 
 []( 
 void 
 &nbsp;*p,&nbsp;size_t&nbsp;size); 
 private 
 : &nbsp;&nbsp;&nbsp;&nbsp; 
 int 
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 float 
 &nbsp;&nbsp;&nbsp;m_fnumber; &nbsp;&nbsp;&nbsp;&nbsp; 
 int 
 &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;arr[SIZE]; }; 
 #endif 
 &nbsp; 
 //&nbsp;OPERATOROVERLOADINGCLASS_H 
 </div> </td> 
 </tr> 
 </tbody> 
</table>

OperatorOverloadingClass.cpp

<table style="font-family:Consolas, 'Courier New';font-size:12px;vertical-align:text-top;line-height:15px;"> 
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 </div> </td> 
 <td>&nbsp;</td> 
 <td style="vertical-align:text-top;color:#000000;"> 
 <div> 
 #include 
 &nbsp; 
 "OperatorOverloadingClass.h" 
 
 #include 
 &nbsp;&lt;QDebug&gt; OperatorOverloadingClass::OperatorOverloadingClass() { &nbsp;&nbsp;&nbsp;&nbsp;m_number&nbsp;=&nbsp; 
 0 
 ; &nbsp;&nbsp;&nbsp;&nbsp;m_fnumber&nbsp;=&nbsp; 
 0 
 . 
 0 
 ; &nbsp;&nbsp;&nbsp;&nbsp; 
 for 
 ( 
 int 
 &nbsp;i&nbsp;=&nbsp; 
 0 
 ;&nbsp;i&nbsp;&lt;&nbsp;SIZE;&nbsp;i++) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;arr[i]&nbsp;=&nbsp;i; &nbsp;&nbsp;&nbsp;&nbsp;} } OperatorOverloadingClass::OperatorOverloadingClass( 
 const 
 &nbsp; 
 int 
 &nbsp;&amp;number, &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 const 
 &nbsp; 
 float 
 &nbsp;&amp;fnumber) &nbsp;&nbsp;&nbsp;&nbsp;:&nbsp;m_number(number) &nbsp;&nbsp;&nbsp;&nbsp;,&nbsp;m_fnumber(fnumber) { &nbsp;&nbsp;&nbsp;&nbsp; 
 for 
 ( 
 int 
 &nbsp;i&nbsp;=&nbsp; 
 0 
 ;&nbsp;i&nbsp;&lt;&nbsp;SIZE;&nbsp;i++) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;arr[i]&nbsp;=&nbsp;i; &nbsp;&nbsp;&nbsp;&nbsp;} } 
 void 
 &nbsp;OperatorOverloadingClass::print() { &nbsp;&nbsp;&nbsp;&nbsp;qDebug()&nbsp;&lt;&lt;&nbsp; 
 "m_number&nbsp;=" 
 &nbsp;&lt;&lt;&nbsp;m_number; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;+( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp; 
 this 
 -&gt;m_number&nbsp;+&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;-( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp; 
 this 
 -&gt;m_number&nbsp;-&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;*( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp; 
 this 
 -&gt;m_number&nbsp;*&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;/( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp; 
 this 
 -&gt;m_number&nbsp;/&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;%( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp; 
 this 
 -&gt;m_number&nbsp;%&nbsp;obj.m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;^( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp;( 
 this 
 -&gt;m_number)&nbsp;^&nbsp;(obj.m_number); &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;&amp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp;( 
 this 
 -&gt;m_number)&nbsp;&amp;&nbsp;(obj.m_number); &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } OperatorOverloadingClass&nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;|( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;out; &nbsp;&nbsp;&nbsp;&nbsp;out.m_number&nbsp;=&nbsp;( 
 this 
 -&gt;m_number)&nbsp;|&nbsp;(obj.m_number); &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;out; } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;&amp;&amp;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;( 
 this 
 -&gt;m_number)&nbsp;&amp;&amp;&nbsp;(obj.m_number); } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;||( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;( 
 this 
 -&gt;m_number)&nbsp;||&nbsp;(obj.m_number); } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;&lt;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 if 
 (m_number&nbsp;&lt;&nbsp;obj.m_number) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 true 
 ; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 false 
 ; } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;&gt;( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 if 
 (m_number&nbsp;&gt;&nbsp;obj.m_number) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 true 
 ; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 false 
 ; } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;&lt;=( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 if 
 (m_number&nbsp;&lt;=&nbsp;obj.m_number) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 true 
 ; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 false 
 ; } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;&gt;=( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 if 
 (m_number&nbsp;&gt;=&nbsp;obj.m_number) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 true 
 ; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 false 
 ; } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;==( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 if 
 (m_number&nbsp;==&nbsp;obj.m_number) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 true 
 ; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 false 
 ; } 
 bool 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp;!=( 
 const 
 &nbsp;OperatorOverloadingClass&nbsp;&amp;obj) { &nbsp;&nbsp;&nbsp;&nbsp; 
 if 
 (m_number&nbsp;!=&nbsp;obj.m_number) &nbsp;&nbsp;&nbsp;&nbsp;{ &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 true 
 ; &nbsp;&nbsp;&nbsp;&nbsp;} &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp; 
 false 
 ; } 
 //&nbsp;overloaded&nbsp;prefix&nbsp;++&nbsp;operator 
 OperatorOverloadingClass&nbsp;OperatorOverloadingClass::&nbsp; 
 operator 
 ++&nbsp;() { &nbsp;&nbsp;&nbsp;&nbsp;++m_number;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;increment&nbsp;this&nbsp;object 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;OperatorOverloadingClass(m_number,&nbsp; 
 0 
 . 
 0 
 ); } 
 //&nbsp;overloaded&nbsp;postfix&nbsp;++&nbsp;operator 
 OperatorOverloadingClass&nbsp;OperatorOverloadingClass::&nbsp; 
 operator 
 ++(&nbsp; 
 int 
 &nbsp;) { &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;save&nbsp;the&nbsp;orignal&nbsp;value 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;T(m_number,&nbsp; 
 0 
 . 
 0 
 ); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;increment&nbsp;this&nbsp;object 
 &nbsp;&nbsp;&nbsp;&nbsp;++m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;return&nbsp;old&nbsp;original&nbsp;value 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;T; } 
 //&nbsp;overloaded&nbsp;prefix&nbsp;--&nbsp;operator 
 OperatorOverloadingClass&nbsp;OperatorOverloadingClass::&nbsp; 
 operator 
 --&nbsp;() { &nbsp;&nbsp;&nbsp;&nbsp;--m_number;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;increment&nbsp;this&nbsp;object 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;OperatorOverloadingClass(m_number,&nbsp; 
 0 
 . 
 0 
 ); } 
 //&nbsp;overloaded&nbsp;postfix&nbsp;--&nbsp;operator 
 OperatorOverloadingClass&nbsp;OperatorOverloadingClass::&nbsp; 
 operator 
 --(&nbsp; 
 int 
 &nbsp;) { &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;save&nbsp;the&nbsp;orignal&nbsp;value 
 &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;T(m_number,&nbsp; 
 0 
 . 
 0 
 ); &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;increment&nbsp;this&nbsp;object 
 &nbsp;&nbsp;&nbsp;&nbsp;--m_number; &nbsp;&nbsp;&nbsp;&nbsp; 
 //&nbsp;return&nbsp;old&nbsp;original&nbsp;value 
 &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;T; } 
 void 
 &nbsp;*OperatorOverloadingClass:: 
 operator 
 &nbsp; 
 new 
 (size_t&nbsp;size) { &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;malloc(size); } 
 void 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp; 
 delete 
 ( 
 void 
 &nbsp;*p) { &nbsp;&nbsp;&nbsp;&nbsp;free(p); } 
 inline 
 &nbsp; 
 void 
 &nbsp;*OperatorOverloadingClass:: 
 operator 
 &nbsp; 
 new 
 [](size_t&nbsp;size) { &nbsp;&nbsp;&nbsp;&nbsp;OperatorOverloadingClass&nbsp;*p&nbsp;=&nbsp;(OperatorOverloadingClass&nbsp;*)malloc(size); &nbsp;&nbsp;&nbsp;&nbsp; 
 return 
 &nbsp;p; } 
 inline 
 &nbsp; 
 void 
 &nbsp;OperatorOverloadingClass:: 
 operator 
 &nbsp; 
 delete 
 []( 
 void 
 &nbsp;*p,&nbsp;size_t&nbsp;size) { &nbsp;&nbsp;&nbsp;&nbsp;free(p); } 
 </div> </td> 
 </tr> 
 </tbody> 
</table>

转载于:https://www.cnblogs.com/MakeView660/p/11102349.html

[1012444-20190628140308422-348786570.png]: /images/20211116/885ba5bb2e8b4504a93b14e98f49dad9.png
[1012444-20190628140322836-1002021228.png]: /images/20211116/71db210b1a1c47aa82cae3debfc529de.png
[Link 1]: http://www.stroustrup.com/bs_faq2.html#overload-dot