Javascript 从JSON数组读取_Javascript_Jquery_Json

Javascript 从JSON数组读取

javascript jquery json

Javascript 从JSON数组读取,javascript,jquery,json,Javascript,Jquery,Json,这是我的JSON数组： msg={"userid":"82","0":"82","first":"A","1":"A","last":"B","2":"B","email":"w@w.com","3":"w@w.com","username":"n","4":"n","password":"o","5":"o","hash":"3242","6":"3242","active":"0","7":"0","date":"0","8":"0","holding":"","9":"","ip":"0"

这是我的JSON数组：

msg={"userid":"82","0":"82","first":"A","1":"A","last":"B","2":"B","email":"w@w.com","3":"w@w.com","username":"n","4":"n","password":"o","5":"o","hash":"3242","6":"3242","active":"0","7":"0","date":"0","8":"0","holding":"","9":"","ip":"0","10":"0","attempts":"0","11":"0"}

现在，我试图得到不同的部分，但我尝试没有工作。我试过了

msg.first //returns undefined
msg['first'] // returns undefined
msg[0] // returns that first bracket {

我相信这很容易解决，我只是不知道问题是什么。这个数组由一些php使用json_encode输出。如果该代码是相关的，请让我知道，我会把它。谢谢

如果msg[0]返回第一个括号，则JSON会被解释为字符串。这可以通过jQuery的parseJSON轻松解决：

我试过了

<html>
<head>
    <script src="http://code.jquery.com/jquery.min.js" type="text/javascript"></script>
    <script type="text/javascript">

    function display(data) {
    $.each(data, function(key,value) {
        $('#userDetails').append('<li>' + key +  " : " +'<span class="ui-li-aside">'+ value +'</span></li>');
    });
}
        $(document).ready(function() {
            msg= {"userid":"82",
                   "0":"82",
                   "first":"A",
                   "1":"A",
                   "last":"B",
                   "2":"B",
                   "email":"w@w.com",
                   "3":"w@w.com",
                   "username":"n",
                   "4":"n",
                   "password":"o",
                   "5":"o",
                   "hash":"3242",
                   "6":"3242",
                   "active":"0",
                   "7":"0",
                   "date":"0",
                   "8":"0",
                   "holding":"",
                   "9":"",
                   "ip":"0",
                   "10":"0",
                   "attempts":"0",
                   "11":"0"}

        display(msg);
        });
    </script>
</head>
<body>
<div id="userDetails"></div>
</body>
</html>

在使用jQueryAjax函数时，我经常遇到这个问题。您需要指定您期望的是json响应

如果进行此调用，则返回的数据变量将是字符串

$.ajax({
    type: "POST",
    url: '/controller/function',
    data: {
        'parameter_name' : value,
    },
    success: function(data){
        console.log(data.blah); // Undefined
    },
});

但是如果将数据类型指定为json，那么数据变量将是json对象

$.ajax({
    dataType: "json", // Have to include this
    type: "POST",
    url: '/controller/function',
    data: {
        'parameter_name' : value,
    },
    success: function(data){
        console.log(data.blah); // Defined!!!
    },
});

如果您的数据实际上在javascript变量中（如您所示），那么在这里似乎可以正常工作：仅供参考，答案中显示的代码不是数组或JSON，而是javascript文本对象声明。JSON是一种文本格式，用于以文本形式交换结构化数据。+1。请注意，尽管all JSON是一个字符串，但问题中显示的代码是一个对象文本，而不是JSON，也不是数组，b如果通过Ajax请求检索JSON，那么jQuery的Ajax方法将自动解析返回的JSON，并将结果对象提供给成功回调。如果/controller/function页面返回内容类型为application/JSON的响应，那么$.Ajax将自动解析它。

$.ajax({
    dataType: "json", // Have to include this
    type: "POST",
    url: '/controller/function',
    data: {
        'parameter_name' : value,
    },
    success: function(data){
        console.log(data.blah); // Defined!!!
    },
});