逗号运算符重载
#include<string>
#include<iostream>
using namespace std;
class Tem{
private:
int x;
public:
Tem(int);
Tem operator ,(Tem);
void display();
};
Tem::Tem(int xx=0){
x = xx;
}
Tem Tem::operator , (Tem t){
cout<<t.x<<endl;
return Tem(t.x);
}
void Tem::display(){
cout<<"Class(Tem) includes of: "<<x<<endl;
}
int main(){
Tem tem1(10);
Tem tem2(20);
Tem other = (tem1,tem2); //会选择第二个 int a= 1,2;a等于2而不是1
other.display();
return 0;
}
取成员运算符重载
#include<iostream>
using namespace std;
class Tem{
public:
int n;
float m;
Tem* operator ->(){
return this;
}
};
int main(){
Tem tem;
tem->m = 10; //调用->运算符，返回Tem*类型并访问m
cout<<"tem.m is "<<tem.m<<endl;
cout<<"tem->m is "<<tem->m<<endl;
return 0;
}
输入输出运算符重载
#include<iostream>
using namespace std;
class Date{
private:
int year,month,day;
public:
Date (int y,int m,int d){
year = y;
month = m;
day = d;
}
friend ostream& operator <<(ostream &stream,const Date &date){
stream<<date.year<<" "<<date.month<<" "<<date.day<<endl;
return stream;
}
friend istream& operator >>(istream &stream,Date &date){
stream>>date.year>>date.month>>date.day;
return stream;
}
};
int main(){
Date _date(2017,6,13);
cout<<_date;
cin>>_date;
cout<<_date;
return 0;
}
下标运算符重载
#include<iostream>
#include<string>
using namespace std;
const int LEN = 3;
class Tem{
private:
int a[LEN];
public:
Tem(){
for (int i=0;i<LEN;++i)
a[i] = i;
}
int &operator [](int i){
return a[i];
}
};
int main(){
Tem tem;
cout<<tem[1]<<endl;
tem[1] = -1;//修改
cout<<tem[1]<<endl;//重新查看
return 0;
}
括号运算符重载
#include<iostream>
#include<string>
using namespace std;
const int LEN = 10;
class Tem{
private:
int a[LEN];
public:
Tem(){
for (int i=0;i<LEN;++i)
a[i] = i;
}
int &operator [](int i){
return a[i];
}
int * operator ()(int start ,int end){ //用括号运算符实现切片操作
int *t = new int [end-start];
for(int i=start;i<end;++i)
t[i-start] = a[i];
return t;
}
};
int main(){
Tem tem;
int *arr = tem(0,5);
for(int i=0;i<5;++i){
cout<<arr[i]<<" ";
}
cout<<endl;
return 0;
}
new和delete运算符重载
#include<iostream>
#include<cstddef>
using namespace std;
const int LEN = 10;
class Tem{
private:
int a[LEN];
public:
Tem(){
for (int i=0;i<LEN;++i)
a[i] = i;
}
void *operator new(size_t size); //开辟大小为size的空间
void *operator new(size_t size,char p); //开辟大小为size的空间，并且每个都赋值为p
void operator delete(void *p);
};
void * Tem::operator new(size_t size){//参数是无符号类型，在cstddef里，是c++里的unsigned
cout<<"Create a place includes of "<<size<<" bytes\n";
char *s = new char[size];
*s = 'a';
return s;
}
void * Tem::operator new(size_t size,char p){ //返回类型是可以自动转化的指针类型
cout<<"Create a place includes of "<<size<<" bytes\n";
char *s = new char[size];
for(int i=0;i<size;i++)
s[i] = p;
return s;
}
void Tem::operator delete(void *p){
cout<<"Delete \n";
delete [] p; //最后释放空间
}
int main(){
Tem *tem = new Tem;
delete tem;
Tem *_tem = new('E') Tem;
delete _tem;
return 0;
}