如何在不使用JQuery，JSON或任何外部库的情况下使用JavaScript在会话存储中存

3回答

犯罪嫌疑人X

JSON不是库，而是一种表示法。花一些时间来阅读它。有一些编码方法。下面有一个简单的示例。获取所有检查的输入及其值：var result = Array.from(document.querySelectorAll('input[type=checkbox]:checked')).map(a => { return { id: a.getAttribute("id"), value: a.value }; });console.log(result);在本地存储中保存和从中检索：var resultInJson = JSON.stringify(result);console.log(resultInJson);localStorage.setItem("data", resultInJson);console.log(localStorage.getItem("data"));console.log(JSON.parse(localStorage.getItem("data")));

FFIVE

没有JSON注意事项的解决方案：const  foodForm = document.querySelector('#food-form'),  StorageName = 'myFoodStorage';foodForm.onchange=()=>{    // = storeFood  let CheckList = Array.from(foodForm.querySelectorAll('input[type=checkbox]')).map(a=>`${a.id}=${a.checked}`);  sessionStorage.setItem(StorageName, CheckList.join(','));}window.onload=()=>{   // = retrieveFood  let CheckList = sessionStorage.getItem(StorageName)  if (CheckList) {    CheckList.split(',').forEach(e=>{      let pair = e.split('=');      document.getElementById('pair[0]').checked = pair[1] === 'true';    })  }}

慕运维8079593

如果要更高级的序列化，请使用此方法，它应适用于所有值为字符串的对象。用于sessionStorage.setItem('foods', serialize(foodStates))存储复选框的状态并用于对其parse(sessionStorage.getItem('foods'))进行重构"use strict";function sanitize(str) {  //Split into char array, escape chars and put back together into string  return str.split('').map(chr => sanitize.map[chr] || chr).join('')}function desanitize(str) {  //Split into char array, escape chars and put back together into string  return str.replace('\\:', ':').replace('\\;', ';').replace('\\\\', '\\')}sanitize.map = {  '\\': '\\\\',  ':': '\\:',  ';': '\\;'}function serialize(obj) {  var result = "";  for(var prop in obj) {    result += `${sanitize(prop)} :${sanitize(obj[prop])} ;`;  }  //Remove last ' ;'  result = result.slice(0, -2);  return result;}function parse(str) {  var obj = {};  for(var part of str.split(' ;')) {    var [key, value] = part.split(' :')    key = desanitize(key)    value = desanitize(value)    obj[key] = value;  }  return obj;}var orgObj = {pizza: "true", hamburger: "false", sandwich: "true"}console.log(orgObj)var encodedString = serialize(orgObj)console.log(encodedString)var newObj = parse(encodedString)console.log(newObj)