**在Chrome浏览器的开发者工具的Console中，输入localStorage就会打印出一系列宿主（浏览器）提供的localStorage自带的方法，摘录了一些常用的API如下表所示：** | 名称 | 功能 | | --- | --- | | clear | 清空localStorage上存储的数据 | | getItem | 读取数据 | | hasOwnProperty | 检查localStorage上是否保存了变量x，需要传入x | | key | 读取第i个数据的名字或称为键值 | | length | localStorage存储变量的个数 | | propertyIsEnumerable | 用来检测属性是否属于某个对象的 | | removeItem | 删除某个具体变量 | | setItem | 存储数据 | | toLocaleString | 将（数组）转为本地字符串 | | valueOf | 获取所有存储的数据 | **清空localStorage** ~~~ localStorage.clear() // undefined localStorage // Storage {length: 0} ~~~ **存储数据** ~~~ localStorage.setItem("name","caibin") //存储名字为name值为caibin的变量 localStorage.name = "caibin"; // 等价于上面的命令 localStorage // Storage {name: "caibin", length: 1} ~~~ **读取数据** ~~~ localStorage.getItem("name") //caibin,读取保存在localStorage对象里名为name的变量的值 localStorage.name // "caibin" localStorage.valueOf() //读取存储在localStorage上的所有数据 localStorage.key(0) // 读取第一条数据的变量名(键值) //遍历并输出localStorage里存储的名字和值 for(var i=0; i<localStorage.length;i++){ console.log('localStorage里存储的第'+i+'条数据的名字为：'+localStorage.key(i)+',值为：'+localStorage.getItem(localStorage.key(i))); } ~~~ **删除某个变量** ~~~ localStorage.removeItem("name"); //undefined localStorage // Storage {length: 0} 可以看到之前保存的name变量已经从localStorage里删除了 ~~~ **检查localStorage里是否保存某个变量** ~~~ // 这些数据都是测试的，是在我当下环境里的，只是demo哦～ localStorage.hasOwnProperty('name') // true localStorage.hasOwnProperty('sex') // false ~~~ **将数组转为本地字符串** ~~~ var arr = ['aa','bb','cc']; // ["aa","bb","cc"] localStorage.arr = arr //["aa","bb","cc"] localStorage.arr.toLocaleString(); // "aa,bb,cc" ~~~ **将JSON存储到localStorage里** ~~~ var students = { xiaomin: { name: "xiaoming", grade: 1 }, teemo: { name: "teemo", grade: 3 } } students = JSON.stringify(students); //将JSON转为字符串存到变量里 console.log(students); localStorage.setItem("students",students);//将变量存到localStorage里 var newStudents = localStorage.getItem("students"); newStudents = JSON.parse(students); //转为JSON console.log(newStudents); // 打印出原先对象 ~~~