如何利用Go语言开发点餐系统的营业时间管理功能

package main

import (
    "fmt"
    "time"
)

type TimeRange struct {
    StartTime time.Time
    EndTime   time.Time
}

type MenuItem struct {
    Name     string
    Price    float64
    TimeRule TimeRange
}

var menuList []MenuItem

func isTimeInRange(t time.Time, tr TimeRange) bool {
    return t.After(tr.StartTime) && t.Before(tr.EndTime)
}

func showMenuByTime() {
    currentTime := time.Now()

    for _, item := range menuList {
        if isTimeInRange(currentTime, item.TimeRule) {
            fmt.Println(item.Name, item.Price)
        }
    }
}

func main() {
    // 初始化菜单列表
    menuList = []MenuItem{
        {Name: "早餐A", Price: 20.5, TimeRule: TimeRange{
            StartTime: time.Date(2022, time.January, 1, 8, 0, 0, 0, time.UTC),
            EndTime:   time.Date(2022, time.January, 1, 10, 0, 0, 0, time.UTC),
        }},
        {Name: "午餐A", Price: 30.0, TimeRule: TimeRange{
            StartTime: time.Date(2022, time.January, 1, 11, 0, 0, 0, time.UTC),
            EndTime:   time.Date(2022, time.January, 1, 14, 0, 0, 0, time.UTC),
        }},
        {Name: "晚餐A", Price: 40.0, TimeRule: TimeRange{
            StartTime: time.Date(2022, time.January, 1, 18, 0, 0, 0, time.UTC),
            EndTime:   time.Date(2022, time.January, 1, 22, 0, 0, 0, time.UTC),
        }},
    }

    showMenuByTime()
}