4.4 Web存储

HTML5：

<1> localStorage 没有时间限制

<2> sessionStorage 针对session数据存储, 浏览器关闭则失效

cookie缺点: cookie不适合大量数据存储

<1> localStorage

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title>localStorage</title>
    <script src="myjavascript.js"></script>
</head>
<body>
    <textarea id="ta" style="200px; height: 200px"></textarea>
    <button id="btn">save</button>
</body>
</html>

var ta;
var button;

window.onload = function(){
    ta = document.getElementById("ta");
    if(localStorage.text)
        ta.value = localStorage.text;

    button = document.getElementById("btn");
    button.onclick = function () {
        localStorage.text = ta.value;
    }
}

　　点击save按钮之后, 刷新页面, 甚至关闭浏览器再打开此页面都会显示mirror

2. sessionStorage

　　跟上面类似