c++ 智能指针的简单实现
作者:互联网
手撕智能指针,emmmmm
show me the code
#include <iostream>
using namespace std;
template<typename T>
class smartPtr {
private:
T* _ptr;
int* _count;
public:
smartPtr(T* ptr = nullptr) :_ptr(ptr), _count(new int(1)) {
cout << "Constructor is called!" << endl;
}
smartPtr(const smartPtr<T>& ptr) :_ptr(ptr._ptr), _count(ptr._count) {
++(*_count);
cout << "Copy constructor is called!" << endl;
}
smartPtr<T>& operator=(const smartPtr<T>& ptr){
++(*ptr._count); //防止自赋值带来的提前释放
if (--(*_count) == 0) {
delete _count;
delete _ptr;
cout << "original object is deleted!" << endl;
}
_ptr = ptr._ptr;
_count = ptr._count;
cout << "Assignment operator overloaded is called!" << endl;
return *this;
}
~smartPtr() {
if (--(*_count) == 0) {
delete _ptr;
delete _count;
_ptr = nullptr;
_count = nullptr;
cout << "Destructor is called!" << endl;
}
}
};
int main()
{
// Test Constructor and Assignment Operator Overloaded
smartPtr<int> p1(new int(0));
p1 = p1;
// Test Copy Constructor
smartPtr<int> p2(p1);
// Test Assignment Operator Overloaded
smartPtr<int> p3(new int(1));
p3 = p1;
return 0;
}
标签:count,p1,cout,int,c++,智能,指针,ptr,smartPtr 来源: https://blog.csdn.net/maoxiaolele/article/details/120102293