如何访问Json中的给定元素

Question

I am new to Json. 我是Json的新手。 please tell me how to access following element. 请告诉我如何访问以下元素。 this is my Json 这是我的杰森

var data = {"student":[{"fname":"mad", "sname":"cha"}, {"fname":"sun", "sname":"ban"}, {"fname":"sha", "sname":"kiri"}]};

so how I access to the "mad" value. 所以我如何获得"mad"价值。

actually this is what I trying to do 其实这就是我想做的

<html>
<head>
<title></title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<script>
    function click_me(){
        var data = {"student":[{"fname":"mad", "sname":"cha"}, {"fname":"sun", "sname":"ban"}, {"fname":"sha", "sname":"kiri"}]};
        localStorage.setItem('my_name',data);
        alert('OK');
    }

    function show_me(){
        var x = localStorage.getItem('my_name');
        x = x.student[0].fname;
        alert(x);
    }
</script>

</head>
<body>
  <input type="button" name="btn" value="Click" onclick="click_me()">
  <input type="button" name="btn" value="show_me" onclick="show_me()">
</body>
</html>

Answer 1

It's 它的

var yourValue = data.student[0].fname

By the way, this isn't JSON but a plain javascript object. 顺便说一下，这不是JSON，而是普通的javascript对象。 JSON is a string based interchange format. JSON是基于字符串的交换格式。

EDIT following your edit. 编辑后进行编辑。

localStorage only stores strings. localStorage仅存储字符串。 That's why getItem gives you a string in which you can't find your "mad". 这就是为什么getItem为您提供一个字符串，在其中您找不到“疯子”的原因。

Here's what you can do : 您可以执行以下操作：

function click_me(){
    var data = {"student":[{"fname":"mad", "sname":"cha"}, {"fname":"sun", "sname":"ban"}, {"fname":"sha", "sname":"kiri"}]};
    localStorage.setItem('my_name', JSON.stringify(data));
    alert('OK');
}

function show_me(){
    var x = JSON.parse(localStorage.getItem('my_name')||"{}");
    x = x.student[0].fname; // it would be cleaner to test x.student exists
    alert(x);
}

Answer 2

Access the value as follows: 如下访问值：

var firstName = data.student[0].fname;

Example: http://jsfiddle.net/N8bSk/ 示例： http ： //jsfiddle.net/N8bSk/

Answer 3

你可以这样做

  var yourValue = data.student[0].fname

如何访问Json中的给定元素

问题描述

3 个解决方案

解决方案1
2 已采纳 2012-12-04 11:42:10

解决方案2
1 2012-12-04 11:42:28

解决方案3
1 2012-12-04 11:44:51

如何访问Json中的给定元素

问题描述

3 个解决方案

解决方案1 2 已采纳 2012-12-04 11:42:10

解决方案2 1 2012-12-04 11:42:28

解决方案3 1 2012-12-04 11:44:51

解决方案1
2 已采纳 2012-12-04 11:42:10

解决方案2
1 2012-12-04 11:42:28

解决方案3
1 2012-12-04 11:44:51