用c语言编写一个外卖系统】

当然可以！以下是一个简单的外卖系统的C语言代码示例：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct MenuItem {
    char name[50];
    float price;
};

struct Order {
    struct MenuItem item;
    int quantity;
};

void displayMenu(struct MenuItem menu[], int size) {
    printf("==== 外卖菜单 ====\n");
    for (int i = 0; i < size; i++) {
        printf("%d. %s - ￥%.2f\n", i+1, menu[i].name, menu[i].price);
    }
}

void placeOrder(struct MenuItem menu[], int size, struct Order orders[], int *orderCount) {
    int choice, quantity;
    
    displayMenu(menu, size);
    
    printf("请选择要点的菜品编号（输入0退出）: ");
    scanf("%d", &choice);
    
    if (choice == 0) {
        printf("已退出外卖系统\n");
        return;
    }
    
    printf("请输入数量: ");
    scanf("%d", &quantity);
    
    if (choice > 0 && choice <= size) {
        struct Order newOrder;
        newOrder.item = menu[choice-1];
        newOrder.quantity = quantity;
        
        orders[*orderCount] = newOrder;
        (*orderCount)++;
        
        printf("已成功下单！\n");
    } else {
        printf("无效的菜品编号！\n");
    }
}

void displayOrder(struct Order orders[], int orderCount) {
    float total = 0.0;
    
    printf("==== 我的订单 ====\n");
    
    for (int i = 0; i < orderCount; i++) {
        struct Order order = orders[i];
        printf("%d. %s - ￥%.2f × %d\n", i+1, order.item.name, order.item.price, order.quantity);
        total += order.item.price * order.quantity;
    }
    
    printf("总计: ￥%.2f\n", total);
}

int main() {
    struct MenuItem menu[5] = {
        {"宫保鸡丁", 25.0},
        {"鱼香肉丝", 20.0},
        {"水煮肉片", 30.0},
        {"回锅肉", 28.0},
        {"麻婆豆腐", 15.0}
    };
    
    struct Order orders[10];
    int orderCount = 0;
    int choice;
    
    while (1) {
        printf("==== 外卖系统 ====\n");
        printf("1. 查看菜单\n");
        printf("2. 下单\n");
        printf("3. 查看订单\n");
        printf("4. 退出\n");
        printf("请输入选择: ");
        scanf("%d", &choice);
        
        switch (choice) {
            case 1:
                displayMenu(menu, sizeof(menu)/sizeof(menu[0]));
                break;
            case 2:
                placeOrder(menu, sizeof(menu)/sizeof(menu[0]), orders, &orderCount);
                break;
            case 3:
                displayOrder(orders, orderCount);
                break;
            case 4:
                printf("谢谢使用，再见！\n");
                exit(0);
            default:
                printf("无效的选择！\n");
                break;
        }
        
        printf("\n");
    }
    
    return 0;
}

这个代码示例实现了一个简单的外卖系统。它包括了菜单的展示、下单、查看订单等功能。你可以根据自己的需求对代码进行修改和扩展。希望对你有帮助！如果有任何问题，请随时提问。