C++运算符重载

阅读数: 10000次

重载

C++运算符重载

加号重载

完整代码：

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#include<iostream>
using namespace std;
//加号运算符重载 
class Person
{
public:
	//成员函数重载+ 
//	Person operator+(Person &p)
//	{
//		Person temp;
//		temp.m_A=this->m_A+p.m_A;
//		temp.m_B=this->m_B+p.m_B;
//		return temp;
//	}
	int m_A;
	int m_B;
};

//全局函数重载
Person operator+(Person &p1,Person &p2)
{
	Person temp;
	temp.m_A=p1.m_A+p2.m_A;
	temp.m_B=p1.m_B+p2.m_B;
	return temp;
}
//测试函数 
void test01()
{
	Person p1,p2;
	p1.m_A=10;
	p1.m_B=10;
	
	p2.m_A=20;
	p2.m_B=30;
	//成员函数本质调用 
	//Person p3=p1.operator+(p2);
	Person p3=p1+p2;//简便写法 
	//全局函数本质调用
	//Person p3=operator+(p1,p2); 
	cout<<"p3.m_A= "<<p3.m_A<<endl;
	cout<<"p3.m_B= "<<p3.m_B<<endl; 
}



int main()
{
	
	test01();
	return 0;
}

左移运算符重载

只能用全局函数重载，不能用成员函数重载

完整代码：

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#include<iostream>
using namespace std;
//加号运算符重载 
class Person
{
public:
	friend ostream & operator<<(ostream &cout,Person &p);//全局函数做友元 
public:  
	Person(int a,int b)
	{
		m_A=a;
		m_B=b;
	}
private:
	int m_A;
	int m_B;
};

//全局函数重载
ostream & operator<<(ostream &cout,Person &p)
{
	cout<<"p.m_A= "<<p.m_A<<endl;
	cout<<"p.m_B= "<<p.m_B<<endl;	
	return cout;
}

//测试函数 
void test01()
{
	Person p(10,20);
	cout<<p<<endl; 
}

int main()
{
	
	test01();
	return 0;
}

递增运算符重载

完整代码

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#include<iostream>
using namespace std;
//自定义类型
class MyInteger
{
//为了能够访问私有权限，要进行全局函数友元化
public: 
    friend ostream & operator<<(ostream &cout,MyInteger &p);
public:
	MyInteger()
	{
		m_num=0;
	}
	//前置递增++i,返回引用是为了一直对一个数据进行操作 
	MyInteger&  operator++()
	{
		++m_num;
		return *this;
	}
	//后置递增i++
	MyInteger operator++(int)//int代表一个站位参数，可以用于区分前置和后置 
	{
		//先 记录当时结果 
		MyInteger temp=*this;
		//后递增 
		m_num++;
		//再返回 值 
		return temp;
	}
private:
	int m_num;
};

//为了能输出，要用到 左移运算符重载
ostream & operator<<(ostream &cout,MyInteger &p)
{
	cout<<"p.m_num= "<<p.m_num<<endl;
	return cout;
} 
//前置递增测试函数 
void test01()
{
	MyInteger Myint;
	cout<<++(++Myint)<<endl;
	cout<<Myint<<endl;
}
//后置递增测试函数 
void test02()
{
	MyInteger Myints;
	cout<< Myints++ <<endl;
	cout<<Myints<<endl;
} 

int main()
{
	//test01();
	test02();
	return 0;
}

递减运算符重载

完整代码

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#include<iostream>
using namespace std;
//递减运算符重载

class MyInteger
{
public:
	friend ostream &operator<<(ostream &cout,MyInteger &p);//全局函数友元化 
	
	MyInteger()//初始化值 
	{
		m_num=5;
	}
	//前置递增--i,返回引用是为了一直对一个数据进行操作 
	MyInteger&  operator--()
	{
		--m_num;
		return *this;
	}
	
private:
	int m_num;
}; 
//左移运算符重载
ostream &operator<<(ostream &cout,MyInteger &p)
{
	cout<<"p.m_num=: "<<p.m_num<<endl;
	return cout;
} 
void test()
{
	MyInteger cnt;
	cout<<--(--cnt)<<endl;
	cout<<cnt<<endl;
}

int main()
{
	test();
	system("pause"); 
	return 0;
}

赋值运算符重载

完整代码：

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#include<iostream>
using namespace std;
//赋值运算符重载 
class Person 
{
public:
	Person(int age)
	{
		m_Age=new int(age); 
	}
	
	//赋值运算符重载
	Person& operator==(Person &p)
	{
		if(m_Age!=NULL)
		{
			delete m_Age;
			m_Age=NULL;
		}
		//深拷贝 
		m_Age=new int(*p.m_Age);
		return *this;//返回自身 
	} 
	~Person()//析构函数用于人为释放 
	{
		if(m_Age!=NULL)
		{
			delete m_Age;
		    m_Age=NULL; 
		}
	}
	int *m_Age;
};


void test()
{
	Person p1(18);
	Person p2(1),p3(12);
	p3=p2=p1;
	cout<<"p1.m_Age=: "<<*p1.m_Age<<endl;
	cout<<"p2.m_Age=: "<<*p2.m_Age<<endl;
	cout<<"p2.m_Age=: "<<*p2.m_Age<<endl;
}
int main()
{
	test();
	system("pause");
	return 0;
}

关系运算符重载

可以用来判断自定义的两个类型是否相等关系包括相等(==)和不相等(!=)

1.关系运算符相等重载

完整代码：

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#include<iostream>
#include<string.h>
using namespace std;
//关系运算符重载 
class Person
{
public:
	Person(string name,int age)
	{
		m_Name=name;
		m_Age=age;
	}
	
	//重载==
	bool operator==(Person &p)
	{
		if(this->m_Name==p.m_Name && this->m_Age==p.m_Age)
		 return true;
		else
		 return false;
	 } 
public:
    string m_Name;
	int m_Age;	
	
};
void test()
{
	Person p1("Tom",18),p2("Marry",18);
	if(p1==p2)
	 cout<<"p1和p2相等"<<endl;
	else
	 cout<<"p1和p2不相等"<<endl;
}
int main()
{
	test();
	system("pause");
	return 0;
}

2.关系运算符不相等重载

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#include<iostream>
#include<string.h>
using namespace std;
class Person
{
public:
	Person(string name,int age)
	{
		m_Name=name;
		m_Age=age;
	}
	//重载！=
	bool operator!=(Person &p)
	{
		if(this->m_Name!=p.m_Name && this->m_Age!=p.m_Age)
		 return true;
		else
		 return false;
	} 
public:
	string m_Name;
	int m_Age;
};

void test()
{
	Person p1("gyh",20);
	Person p2("wjh",19);
	if(p1!=p2)
	 cout<<"p1和p2不相等"<<endl;
	else
	 cout<<"p1和p2相等"<<endl;
		
}
int main()
{
	test();
	system("pause");
	return 0;
}

函数调用运算符重载

调用比较灵活，和函数调用非常相似

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#include<iostream>
#include<string.h>
using namespace std;
//函数调用运算符()重载 
class Print 
{
public:
	void operator()(string sss)
	{
		cout<<sss<<endl;
	}
	int operator()(int a,int b)
	{
		return a+b;
	}
};

void test1()
{
	Print print;
	print("我想你了");
	//或者
	Print()("我想你了");
}
void test2()
{
	Print add;
	int end=add(10,13);
	cout<<"add= "<<end<<endl;
	//或者
	cout<<Print()(10,24)<<endl; 
}

int main()
{
	test2();
	system("pause");
	return 0;
}
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    缺失模块。
    1、请确保node版本大于6.2
    2、在博客根目录（注意不是yilia根目录）执行以下命令：
    npm i hexo-generator-json-content --save

    3、在根目录_config.yml里添加配置： 

      jsonContent:
    meta: false
    pages: false
    posts:
      title: true
      date: true
      path: true
      text: false
      raw: false
      content: false
      slug: false
      updated: false
      comments: false
      link: false
      permalink: false
      excerpt: false
      categories: false
      tags: true

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