时间:2022-09-08 09:00:22 | 栏目:C代码 | 点击:次
前言:
制造通用模板,创建自定义的数组,
一个数组,里面有这么几个属性,数组容量,数组元素个数,数组本身内存地址,这几个数据都是定义私有类型,提供有参构造,让用户可以构造出这个数组对象。下面是有参构造和拷贝构造和析构函数还有operator=重载的代码
在前面类模板中成员函数创建有这个主意问题,最好的办法就是把类模板写在一个hpp的文件中,不要拆开写成多个文件
#pragma once #include<iostream> using namespace std; #include<string> template<class T> class Myarry { public: Myarry() {};//自己创建有参构造,编译器就不提供无参构造,所以必须自己写一次无参构造,即使是空实现也要写! Myarry(int capacity)//有参构造函数 { this->capacity = capacity; this->size = 0; this->marry = new T[this->capacity];//把数组创建在堆区 } ~Myarry()//析构函数 { if (this->marry !=NULL) { delete []this->marry;//析构数组必须加[],否则会引发断点 marry = NULL; this->capacity = 0; this->size = 0; } } Myarry(const Myarry& arr)//拷贝构造 { this->capacity = arr.capacity; this->size = arr.size; this->marry = new T[arr.capacity]; for (int i = 0; i < arr.size; i++)//把数据拷贝过来 { this->marry[i] = arr->marry[i]; } } //等号赋值 Myarry& operator=(const Myarry& arr) { if (this->marry != NULL)//如果有数据先清空,再赋值 { delete[]this->marry; this->marry = NULL; this->size = 0; this->capacity = 0; } this->capacity = arr.capacity; this->size = arr.size; this->marry = new T[this->capacity]; for (int i = 0; i < this->size; i++)//将数据进行拷贝 { this->marry[i] = arr.marry[i]; } return *this; } void pushback(const T&ptr)//尾加法 { if (this->capacity == this->size) { cout << "容量已满!" << endl; return; } this->marry[this->size] = ptr; this->size++; } void deleteback()//尾删法 { if (this->size == 0) { cout << "数据为零,没有可删数据!" << endl; } delete this->marry[this->size - 1]; this->size--; } T & operator[](int index)//通过下标访问数组,并使它作为左值加& { if (index > this->capacity) { cout << "访问越界!" << endl; exit(0); } return this->marry[index]; } int gercapacity()//获取数组容量 { return this->capacity; } int getsize()//获取数组元素个数 { return this->size; } private: T * marry;//数组 int capacity;//数组容量 int size;//数组元素个数 };
#include "自定义数组.hpp" class person { public: person() { this->age = 0; } int age; string name; }; void text01() { person p[4]; p[0].age = 20; p[0].name = "张三"; p[1].age = 0; p[1].name = "李四"; p[2].age = 40; p[2].name = "王五"; p[3].age = 80; p[3].name = "赵六"; Myarry<person>pp(10); for (int i = 0; i < 4; i++) { pp.pushback(p[i]); } for (int i = 0; i < pp.getsize(); i++) { cout << pp[i].name<<pp[i].age<< endl; } } void text02() { Myarry<int>inta(10); for (int i = 0; i < 5; i++) { inta.pushback(i); } for (int i = 0; i < inta.getsize(); i++) { cout << inta[i] << endl; } } int main() { /*text02();*/ text01(); return 0; }