C++ 类模板案例 - 数组类封装

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MyArray.hpp

// Created by chenh on 2023/1/14.

#ifndef TEMPLATE_MYARRAY_H
#define TEMPLATE_MYARRAY_H


#include <iostream>
#include <string>

using namespace std;

template<class T>
class MyArray {
public:
    MyArray(int capacity) {
        cout << "parameter constructor" << endl;
        this->_size = 0;
        this->_capacity = capacity;
        this->_array = new T [this->_capacity];
    }

    MyArray(const MyArray &obj) {
        cout << "copy constructor" << endl;
        this->_array = new T [obj._capacity];
        this->_size = obj._size;
        this->_capacity = obj._capacity;
        for (int i = 0; i < this->_size; ++i) {
            this->_array[i] = obj._array[i];
        }
    }

    ~MyArray() {
        cout << "destruction" << endl;
        delete[] this->_array;
    }

    MyArray &operator=(const MyArray &obj) {
        cout << "operator overloading" << endl;
        if (this->_array != NULL) {
            delete[] this->_array;
        }
        this->_array = new T[obj._capacity];
        this->_size = obj._size;
        this->_capacity = obj._capacity;
        for (int i = 0; i < this->_size; ++i) {
            this->_array[i] = obj._array[i];
        }
        return *this;
    }

    T &operator[](int index) {
        if (index <= this->_size) return this->_array[index];
    }

    void push(T data) {
        if (this->_size < this->_capacity)
            this->_array[this->_size++] = data;
    }

    void pop(T data) {
        if (this->_size > 0) {
            this->_size--;
        }
    }

    int get_size() {
        return this->_size;
    }

    int get_capacity() {
        return this->_capacity;
    }

private:
    T *_array;
    int _size;
    int _capacity;
};

#endif // TEMPLATE_MYARRAY_H

main.cpp

#include <iostream>
#include <string>

#include "MyArray.hpp"

using namespace std;

template<class T1, class T2>
class Person {
public:
    Person() {};
    Person(T1 name, T2 age) {
        this->name = name;
        this->age = age;
    }

    T1 name;
    T2 age;
};

void printArray(MyArray<int> &p) {
    for (int i = 0; i < p.get_size(); ++i) {
        cout << p[i] << " ";
    }
    cout << endl;
}

void test01() {
    MyArray<int> p1(5);
    for (int i = 0; i < p1.get_capacity(); ++i) {
        p1.push(i);
    }
    printArray(p1);
}

void printArray(MyArray<Person<string, int>> &arr) {
    for (int i = 0; i < arr.get_size(); ++i) {
        cout << "name: " << arr[i].name << " age:" << arr[i].age << endl;
    }
}

void test02() {
    Person<string, int> p1("Tang monk", 40);
    Person<string, int> p2("Monkey king", 9999);
    Person<string, int> p3("Pigsy", 5000);
    Person<string, int> p4("Sandy", 3000);
    MyArray<Person<string, int>> arr(5);

    arr.push(p1);
    arr.push(p2);
    arr.push(p3);
    arr.push(p4);
    arr.pop(p4);

    printArray(arr);

}

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

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