STL：模板类手写数组

#include
using namespace std;template<class T>
class MyArray {friend void test01();//友元函数
public:MyArray(int capacity)//构造函数{this->mCapacity &＃61; capacity;this->mSize &＃61; 0;//申请空间this->ptr &＃61; new T[this->mCapacity];}MyArray(const MyArray<T>& another)//拷贝函数{this->mCapacity &＃61; another.mCapacity;this->mSize &＃61; another.mSize;//申请空间this->ptr &＃61; new T[this->mCapacity];//开始拷贝for (int i &＃61; 0; i < this->mSize; i&＃43;&＃43;){this->ptr[i] &＃61; another.ptr[i];}}T& operator[](int index)// []操作符重载{return this->ptr[index];}MyArray<T>& operator&＃61;(const MyArray<T>& another)// &＃61;操作符重载{//原本容器有值if (this->ptr !&＃61; nullptr) {delete[] this->ptr;this->ptr &＃61; nullptr;this->mCapacity &＃61; 0;this->mSize &＃61; 0;}this->mCapacity &＃61; another.mCapacity;this->mSize &＃61; another.mSize;this->ptr &＃61; new T[this->mCapacity];for (int i &＃61; 0; i < this->mSize; i&＃43;&＃43;){this->ptr[i] &＃61; another.ptr[i];}return *this;}void PushBack(T& data) {//一个&是对左值取引用//判断容器中是否有位置if (this->mCapacity <&＃61; this->mSize) {return ;}this->ptr[this->mSize] &＃61; data;this->mSize&＃43;&＃43;;}void PushBack(T&& data) {//两个&&是对右值取引用//判断容器中是否有位置if (this->mCapacity <&＃61; this->mSize) {return ;}this->ptr[this->mSize] &＃61; data;this->mSize&＃43;&＃43;;
}~MyArray() {if (this->ptr !&＃61; nullptr) {delete[] this->ptr;this->ptr &＃61; nullptr;this->mCapacity &＃61; 0;this->mSize &＃61; 0;}}
private://一共可以存储多少元素int mCapacity;//现在有多少元素int mSize;//保存数据的首地址T* ptr;
};
void test01() {//测试构造函数MyArray<int> marray(20);int a &＃61; 10, b &＃61; 20, c &＃61; 30;//测试数组内添加元素//对左值取引用marray.PushBack(a);marray.PushBack(b);marray.PushBack(c);//对右值取引用marray.PushBack(1);marray.PushBack(2);marray.PushBack(3);//测试[ ]操作符重载for (int i &＃61; 0; i < marray.mSize; i&＃43;&＃43;) {cout << marray[i] << " ";}
}int main() {test01();
}