1.模板起源

1.模板的定义

1.针对函数属性模板

//针对函数属性
template <class VOID >
VOID print1(int a) {
	cout << a << endl;
}

2.针对数据属性模板

//针对数据属性
template <typename INT,typename FLOAT>
void print2(INT a,FLOAT b) {
	cout << a << b << endl;
}

3.main

int main() {
	print1<void>(1);
	print2<int,float>(2,3.3);
}

结果：

2.模板与重载的结合

1.class MM

class MM {
public:
	MM() {}
	MM(int age,string name):age(age),name(name) {}
	int getAge() {
		return age;
	}
	string getName() {
		return name;
	}
private:
	int age;
	string name;
};

2.模板与流重载的匹配

template<class XX>
void print(XX a) {
	cout << a << endl;
}
ostream& operator<<(ostream& out,MM mm) {
	out << mm.getAge() << mm.getName() << endl;
	return out;
}

3.main

int main() {
	MM mm[3] = { {12,"女生"},{18,"女神"},{23,"女汉子"} };
	cout << mm[0] << mm[1] << mm[2] << endl;
	return 0;
}

结果：

补充：我们可以对流重载使用友元函数，解决无法访问内部类的问题

1.class MM

class MM {
	//友元类
	friend ostream& operator<<(ostream& out, MM mm);
private:
public:
	MM() {}
	MM(int age,string name):age(age),name(name) {}
	int age;
	string name;
};

2.模板与流重载

template<class XX>
void print(XX a) {
	cout << a << endl;
}
ostream& operator<<(ostream& out,MM mm) {
	out << mm.age << mm.name << endl;
	return out;
}

3.main

int main() {
	MM mm[3] = { {12,"女生"},{18,"女神"},{23,"女汉子"} };
	cout << mm[0] << mm[1] << mm[2] << endl;
	return 0;
}

结果：

3.模板类

继承模板类后，成员函数与子类都需要加模板申明，麻烦很少用