解析嵌套的json对象 [英] parsing nested json object

问题描述

我有一个json文件，我正试图从中获取值。一个对象嵌套在此文件中的另一个对象中。我可以隔离顶级值，但不能隔离嵌套值。它必须是语法问题。这是我正在使用的。

I have a json file that I'm trying to get values out of. One object is nested inside another in this file. I can isolate the top level values, but not the nested values. It must be a syntax issue. Here's what I'm using.

这是json：

{
    "total": [
        [
            {
                "votes": "79,060"
            },
            {
                "percent": "11%"
            },
            {
                "winner": "0"
            }
        ],
        [
            {
                "votes": "167,800"
            },
            {
                "percent": "22%"
            },
            {
                "winner": "0"
            }
        ],
        [
            {
                "votes": "51,519"
            },
            {
                "percent": "7%"
            },
            {
                "winner": "0"
            }
        ],
        [
            {
                "votes": "297,060"
            },
            {
                "percent": "39%"
            },
            {
                "winner": "1"
            }
        ],
        [
            {
                "votes": "156,787"
            },
            {
                "percent": "21%"
            },
            {
                "winner": "0"
            }
        ]
    ],
    "useWinnerColors": 1,
    "timestamp": "3:00 p.m. April 26",
    "candidateCount": 5
}

当我写作：

console.log(json.candidateCount);

我得到了正确的答案（5）。

I get the right answer (5).

但是当我写的时候：

console.log(json.total[0][1]);

我得到对象{percent =11％}。

I get Object { percent="11%"}.

当我写：

console.log(json.total[0].votes);

我得到了未定义。

如何隔离总计项目的价值？

How do I isolate the value of the items in "total", please?

推荐答案

你得到 undefined 因为 json.total [0] 本身就是一个数组。你需要隔离 <$ em> c> json.total [0] 里面的特定数组。所以你需要做类似 json.total [0] [0] .votes 或 json.total [0] [1] .votes 。

You're getting undefined because json.total[0] is itself, an array. You need to isolate the specific array inside json.total[0]. So you would need to do something like json.total[0][0].votes or json.total[0][1].votes.

我认为更好的结构你的JSON将是这样的：

I think a better structure for your JSON would be something like this:

{"total": [    
   {
      "votes": "79,060"
      "percent": "11%"
      "winner": "0",
   },
   ...
   {
      "votes": "156,787",
      "percent": "21%",
      "winner": "0"
   }], 
   "useWinnerColors": 1,
   "timestamp": "3:00 p.m. April 26",
   "candidateCount": 5
}

现在你可以执行 json.total [0] .votes 。

您不需要为每个条目创建一个数组是名称 - 值对。您可以直接使用关联数组。

You don't need to create an array where each entry is a name-value pair. You can directly use an associative-array.

编辑：要迭代关联数组，请使用 for..in 以及 hasOwnProperty（）。 hasOwnProperty（） check将阻止您迭代它继承的属性（某些第三方库污染命名空间）：

EDIT: To iterate over your associative array, use for..in along with hasOwnProperty(). The hasOwnProperty() check will prevent you from iterating over properties that it has inherited (some third-party libraries pollute the namespace):

var map = json.total[0];
for(var prop in map) if(map.hasOwnProperty(prop)) {
   var value = map[prop];
   ...
}

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