Java实现简易购物车系统教程

public class Product {
    private int id;
    private String name;
    private double price;
public Product(int id, String name, double price) {
    this.id = id;
    this.name = name;
    this.price = price;
}

// Getter方法
public int getId() { return id; }
public String getName() { return name; }
public double getPrice() { return price; }

@Override
public String toString() {
    return "ID: " + id + ", 名称: " + name + ", 价格: ¥" + price;
}
}

import java.util.ArrayList;
import java.util.List;
public class ShoppingCart {
private List items;
public ShoppingCart() {
    items = new ArrayList<>();
}

// 添加商品
public void addItem(Product product) {
    items.add(product);
    System.out.println("已添加: " + product.getName());
}

// 根据ID删除商品
public boolean removeItem(int productId) {
    for (Product item : items) {
        if (item.getId() == productId) {
            items.remove(item);
            System.out.println("已移除: " + item.getName());
            return true;
        }
    }
    System.out.println("未找到ID为 " + productId + " 的商品");
    return false;
}

// 显示购物车内容
public void viewCart() {
    if (items.isEmpty()) {
        System.out.println("购物车为空");
    } else {
        System.out.println("\n--- 购物车内容 ---");
        for (Product item : items) {
            System.out.println(item);
        }
        System.out.println("总计: ¥" + getTotalPrice());
    }
}

// 计算总价
public double getTotalPrice() {
    return items.stream().mapToDouble(Product::getPrice).sum();
}
}

import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
ShoppingCart cart = new ShoppingCart();
    // 模拟一些商品
    Product p1 = new Product(1, "苹果", 5.0);
    Product p2 = new Product(2, "香蕉", 3.5);
    Product p3 = new Product(3, "牛奶", 8.0);

    System.out.println("欢迎使用购物车系统！");
    while (true) {
        System.out.println("\n可选操作:");
        System.out.println("1. 浏览商品");
        System.out.println("2. 添加商品到购物车");
        System.out.println("3. 查看购物车");
        System.out.println("4. 删除商品");
        System.out.println("5. 退出");
        System.out.print("请选择: ");

        int choice = input.nextInt();

        switch (choice) {
            case 1:
                System.out.println("\n--- 商品列表 ---");
                System.out.println(p1);
                System.out.println(p2);
                System.out.println(p3);
                break;

            case 2:
                System.out.print("输入商品ID添加到购物车: ");
                int addId = input.nextInt();
                if (addId == 1) cart.addItem(p1);
                else if (addId == 2) cart.addItem(p2);
                else if (addId == 3) cart.addItem(p3);
                else System.out.println("无效ID");
                break;

            case 3:
                cart.viewCart();
                break;

            case 4:
                System.out.print("输入要删除的商品ID: ");
                int removeId = input.nextInt();
                cart.removeItem(removeId);
                break;

            case 5:
                System.out.println("谢谢使用！");
                input.close();
                return;

            default:
                System.out.println("无效选择，请重试");
        }
    }
}
}