数据存储——localstorage

一、存储数据
HTML中
 <div  id="test"></div>

JS中
localStorage.setItem("key",2);
let a = document.createElement("p");
let test = document.getElementById("test");
test.appendChild(a);
a.innerHTML = localStorage.getItem("key");

   <div id="test">

        </div>

let value = [1, 2, 3];
            function save(name, value) {
                if (typeof value == "object") {
                    localStorage[name] = JSON.stringify(value);
                } else {
                    localStorage[name] = value;
                }
            }

            function get(name, defaultValue) {
                let value;
                if (!localStorage[name]) {
                    value = defaultValue;
                } else {
                    value = JSON.parse(localStorage[name]);
                }
                return value;
            }
            save("s", value);//存储数据
            let a = document.createElement("p");//创建一个p元素
            let test = document.getElementById("test");//获取到div元素
            test.appendChild(a);//将p添加到div元素中
            a.innerHTML = get("s");//p的元素内容解析为本地存储的值