浏览器本地储存

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>localStorage</title>
</head>
<body>
    <h2>localStorage</h2>
    <button onclick="saveData()">点我保存一个数据</button>
    <button onclick="getData()">点我读取一个数据</button>
    <button onclick="delData()">点我删除一个数据</button>
    <button onclick="clearData()">点我清空所有数据</button>

    <script type="text/javascript">
        // 保存数据,浏览器关闭，数据也在
        function saveData(){
            //key 和 value均为字符串
            window.localStorage.setItem('msg','hello!')
            localStorage.setItem('msg2',666)//会自动转成字符串存储
            let p = {name:'张三',age:20}
            localStorage.setItem('msg3',JSON.stringify(p))//会自动转成字符串存储
        }

        function getData(){
            // 读取数据
            const msg3 = localStorage.getItem('msg3')
            console.log(msg3);
        }
        function delData(){
            // 删除数据
            localStorage.removeItem('msg2')
        }
        function clearData(){
            // 清空数据
            localStorage.clear()
        }

    </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>sessionStorage</title>
</head>
<body>
    <h2>sessionStorage</h2>
    <button onclick="saveData()">点我保存一个数据</button>
    <button onclick="getData()">点我读取一个数据</button>

    <script type="text/javascript">
        // 保存数据，数据只保存在一次会话中
        function saveData(){
            //key 和 value均为字符串
            window.sessionStorage.setItem('msg','hello!')
            sessionStorage.setItem('msg2',666)//会自动转成字符串存储
            let p = {name:'张三',age:20}
            sessionStorage.setItem('msg3',JSON.stringify(p))//会自动转成字符串存储
        }

        function getData(){
            // 读取数据
            const msg3 = sessionStorage.getItem('msg3')
            console.log(msg3);
        }

    </script>
</body>
</html>