c++对象和类距举例

#include

using namespace std;

/*
继承
封装
多态

类的访问权限
*/

class bank_account
{	
public:
	//函数名与类名相同，就是构造函数,不能与有返回值（void返回值是空)
	//用于初始化,由系统调用
	bank_account(int acc_num, double amount);
	void open(int acc_num,double amount);//开户
	void deposite(double amount);//存钱
	void withdraw(double amount);//取钱
	void display_balance();//显示私有的内容，接口
private:
	int account_number;//账号
	double  balance;//余额
};

bank_account::bank_account(int acc_num, double amount)
{
	account_number = acc_num;
	balance = amount;
}

void bank_account::open(int acc_num, double amount)
{
	account_number = acc_num;
	balance = amount;
}
void bank_account::display_balance()
{
	cout << "account_number : " << account_number << endl;
	cout << "balance : " << balance << endl;
}
void bank_account::deposite(double amount)
{
	balance -= amount;
}
void bank_account::withdraw(double amount)
{
	balance += amount;
}
/*
//这种定义只是全局的，不是类里面的函数
void open(int acc_num, double amount)
{

}
*/
int main()
{
	bank_account account(1,100.00);
	account.display_balance();
	account.open(1, 200);

	
}