函数和结构体

* 传递和返回结构、传递结构的地址*

#include <iostream>
using namespace std;
struct order {
    char *order_num;
    char *user_name;
    string address;
};
/**
 * 当结构比较小时使用值传递
 */
void print_order(const order order) {
    cout << "order_num = " << order.order_num << endl;
    cout << "user_name = " << order.user_name << endl;
    cout << "address = " << order.address << endl;
}
/**
 * 传递地址,由于函数不修改结构内容，使用const修饰符
 */
void print_order(const order *order) {
    cout << "order_num = " << order->order_num << endl;
    cout << "user_name = " << order->user_name << endl;
    cout << "address = " << order->address << endl;
}
/**
 * 返回结构
 */
order build_order(char *order_num, char *user_name, string address) {
    order ord;
    ord.order_num = order_num;
    ord.user_name = user_name;
    ord.address = address;
    return ord;
}
int main() {
    //测试结构传递
    order o1 = { "020134242", "user_1", "chengDu" };
    print_order(o1);
    print_order(&o1);
    //测试返回结构
    order o2 = build_order("123", "wyl", "chengDu");
    print_order(o2);
    return 0;
}