javascript - JS : Load localstorage in other page

Question

我需要从本地存储加载一个数组。

我将表单输入添加到本地存储的数组中，如下所示:

document.querySelector("#addMeal").addEventListener("click", newMeal);
function newMeal(e){
e.preventDefault();

let title = document.querySelector("#title").value;
let img = document.querySelector("#img").value;
let book = document.querySelector("#book").value;
let calories = document.querySelector("#calories").value;
let servings = document.querySelector("#servings").value;
let type = document.querySelector("#type").value;
let price = document.querySelector("#price").value;
let cook = document.querySelector("#cook").value;
let quantity = document.querySelector("#quantity").value;

let newMeal={
    id: 23,
    title: title,
    img: img,
    book: book,
    calories: calories,
    servings: servings,
    type: type,
    price: price,
    cook: cook,
    quantity: quantity};
meals.push(newMeal);
console.log(meals);

// Put the object into storage
localStorage.setItem('meals', JSON.stringify(meals));}

现在我需要将该数组加载到另一个页面中。我已经有了这部分代码，但这不起作用。有谁知道我做错了什么？

document.addEventListener('DOMContentLoaded', loadMeals);

function loadMeals() {
let retrievedObject = localStorage.getItem('meals');
console.log(meals);
let i = 0;
let id = 1;
let fillMealList = document.querySelector("#fillMealList");
for (let i = 0; i < meals.length; i++) {
    let item = meals.find(item => item.id === id);
    fillMealList.innerHTML +=
        "<article class='objectP'>"+
        "<h3>" + item.title + "</h3>"+
        "<figure>"+
        "<img src='images/" + item.img + "'" +">" +
        "<figcaption>"+
        "Meal by: " +"<span>" + item.cook + "</span>" +
        "</figcaption>" +
        "</figure>"+
        "<div class='info'>"+
        "<p>€ <span>" + item.price + "</span>" + "/pp" + "</p>" +
        "<a href='javascript:addToCart(" + item.id + ")' class='addToCart'>Order</a>"+
        "</div>"+
        "</article>";
    id++;
}}

Answer 1

据我所知，你有 4 个错误。

首先，您需要解析从本地存储收到的字符串。

let retrievedObject = JSON.parse(localStorage.getItem('meals'));

其次，console.log(meals); 可能会抛出错误，因为我在该范围内看不到meals。

第三，将食物放入 localStorage 的行有一个错误的分号。它会抛出一个错误。尝试将分号放在行尾。

localStorage.setItem('meals', JSON.stringify(meals));

第四个可能是您遇到的与第二个问题类似的主要问题。如果meals没有定义为数组，则不能使用它的原型(prototype)方法push，它会抛出错误。添加常量膳食 = []。