C++中类模板的应用你了解多少
时间：2022-06-25 08:07:35|栏目：C代码|点击： 次
类模板应用
数组类的封装
属性：
1，T *pAddress 指向堆区数组的指针。 2，int m_Capacity 数组容量 3，int m_Size 数组大小
行为：
1,myArray(int capacity) 构造函数 2,myArray(const MyArray&arr) 拷贝构造函数 3,operator= 重载赋值操作符= 4,operator[] 重载中括号[] 5,~myArray() 析构函数 6,getCapacity 获取容量 7,getSize 获取大小 8,pushback 尾插
将头文件与实现文件写到一起，后缀是.hpp
Int的.hpp文件
#pragma once
#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
using namespace std;
#include<string>
template<class T>
class MyArray
{
public:
MyArray() {};//默认构造
MyArray(int capacity)//有参构造
{
this->m_Capacity = capacity;
this->m_Size = 0;
this->pAddress = new T[this->m_Capacity];
}
MyArray(const MyArray& arr)//拷贝构造
{
this->m_Capacity = arr.m_Capacity;
this->m_Size = arr.m_Size;
this->pAddress = new T[this->m_Capacity];//这个不能直接拷贝，需要自己重新创建
for (int i = 0; i < arr.m_Size; i++)//然后将数组的元素一个个的赋值过来
{
this->pAddress[i] = arr.pAddress[i];
}
}
MyArray& operator=(const MyArray &arr)//重载赋值操作符=（返回自身的引用）
{
if (this->pAddress)//如果原先有数据了，那么就删除
{
delete[] this->pAddress;
this->pAddress = NULL;
}
//然后进行深拷贝
this->m_Capacity = arr.m_Capacity;
this->m_Size = arr.m_Size;
this->pAddress = new T[this->m_Capacity];//这个不能直接拷贝，需要自己重新创建
for (int i = 0; i < arr.m_Size; i++)//然后将数组的元素一个个的赋值过来
{
this->pAddress[i] = arr.pAddress[i];
}
return *this;
}
T& operator[](int dex)//重载[] 为了访问数组中的值，
{
return this->pAddress[dex];
}
void pushBack(const T& val)//尾插
{
if (this->m_Capacity <= this->m_Size)//如果已经超过范围了
{
return;
}
this->pAddress[this->m_Size] = val;
this->m_Size++;
}
int getCapacity()//获取数组容量
{
return this->m_Capacity;
}
int getSize()//获取数组大小
{
return this->m_Size;
}
~MyArray()//析构
{
if (this->pAddress)
{
delete[] this->pAddress;
this->pAddress = NULL;
}
}
private:
T* pAddress;//指向堆区真实数组指针
int m_Capacity;//数组容量
int m_Size;
};
int的测试文件
#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
using namespace std;
#include<string>
#include"myArray.hpp"
void myPrint(MyArray<int> &myIntArray)
{
for (int i = 0; i < myIntArray.getSize(); i++)
{
cout << myIntArray[i] << endl;
}
}
int main()
{
MyArray<int> myIntArray(100);
for (int i = 0; i < 10; i++)
{
myIntArray.pushBack(i + 100);
}
myPrint(myIntArray);
return 0;
}
输出结果:
100
101
102
103
104
105
106
107
108
109
以上代码证明写的数组类的封装对内置数据类型是适用的，接下来试试自定义类型Person
ps：如果识别出来了是要开辟Person类的数组的空间，需要调用Person的默认构造（有参构造不行），所以必须在Person类中加一个默认构造。
Person类的.hpp文件
#pragma once
#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
using namespace std;
#include<string>
template<class T>
class MyArray
{
public:
MyArray() {};//默认构造
MyArray(int capacity)//有参构造
{
this->m_Capacity = capacity;
this->m_Size = 0;
this->pAddress = new T[this->m_Capacity];
}
MyArray(const MyArray& arr)//拷贝构造
{
this->m_Capacity = arr.m_Capacity;
this->m_Size = arr.m_Size;
this->pAddress = new T[this->m_Capacity];//这个不能直接拷贝，需要自己重新创建
for (int i = 0; i < arr.m_Size; i++)//然后将数组的元素一个个的赋值过来
{
this->pAddress[i] = arr.pAddress[i];
}
}
MyArray& operator=(const MyArray &arr)//重载赋值操作（返回自身的引用）
{
if (this->pAddress)//如果原先有数据了，那么就删除
{
delete[] this->pAddress;
this->pAddress = NULL;
}
//然后进行深拷贝
this->m_Capacity = arr.m_Capacity;
this->m_Size = arr.m_Size;
this->pAddress = new T[this->m_Capacity];//这个不能直接拷贝，需要自己重新创建
for (int i = 0; i < arr.m_Size; i++)//然后将数组的元素一个个的赋值过来
{
this->pAddress[i] = arr.pAddress[i];
}
return *this;
}
T& operator[](int dex)//重载[] 为了访问数组中的值，
{
return this->pAddress[dex];
}
void pushBack(const T& val)//尾插
{
if (this->m_Capacity <= this->m_Size)//如果已经超过范围了
{
return;
}
this->pAddress[this->m_Size] = val;
this->m_Size++;
}
int getCapacity()//获取数组容量
{
return this->m_Capacity;
}
int getSize()//获取数组大小
{
return this->m_Size;
}
~MyArray()//析构
{
if (this->pAddress)
{
delete[] this->pAddress;
this->pAddress = NULL;
}
}
private:
T* pAddress;//指向堆区真实数组指针
int m_Capacity;//数组容量
int m_Size;
};
Person类的测试文件
#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
using namespace std;
#include<string>
#include"myArray.hpp"
class Person
{
public:
Person() {};
string m_name;
int m_age;
Person(string name, int age)
{
this->m_age = age;
this->m_name = name;
}
};
void myPrintInt(MyArray<int> &myIntArray)//int的
{
for (int i = 0; i < myIntArray.getSize(); i++)
{
cout << myIntArray[i] << endl;
}
}
void myPrintPerson(MyArray<Person>& myPersonArray)//Person的
{
for (int i = 0; i < myPersonArray.getSize(); i++)
{
cout << myPersonArray[i].m_name << " " << myPersonArray[i].m_age << endl;
}
}
int main()
{
/*MyArray<int> myIntArray(100);
for (int i = 0; i < 10; i++)
{
myIntArray.pushBack(i + 100);
}
myPrintInt(myIntArray);*/
MyArray<Person>myPersonArray(100);
Person p1("小明", 18);
Person p2("小宏", 18);
Person p3("小量", 19);
Person p4("小应", 18);
myPersonArray.pushBack(p1);
myPersonArray.pushBack(p2);
myPersonArray.pushBack(p3);
myPersonArray.pushBack(p4);
myPrintPerson(myPersonArray);
cout << "数组容量:"<<myPersonArray.getCapacity()<< endl;//100
cout << "数组大小:" << myPersonArray.getSize() << endl;//4
return 0;
}
