Question

我有一个我正在研究的项目，但我对Javascript / Jquery / Ajax知之甚少，而且我很难弄清楚我需要做什么，并且我周围没有人真的要问。使用下面的JSON信息，我需要包含一个Ajax调用来填充当前＆＃39; condition.temp'，返回的温度＆＃39;单位，并设置要链接到的天气链接＆＃39;键入返回的响应。我想把它还给控制台。我已将其设置为将所有JSON数据返回到控制台，但我仍然坚持如何只返回我需要的特定数据项。

{
  "success": true,
  "data": [
    {
      "units": {
        "distance": "mi",
        "speed": "mph",
        "pressure": "in",
        "temperature": "F"
      },
      "language": "en-us",
      "description": "Yahoo! Weather for Paducah, KY, US",
      "astronomy": {
        "sunrise": "5:45 am",
        "sunset": "7:57 pm"
      },
      "item": {
        "forecast": [
          {
            "day": "Mon",
            "text": "Mostly Cloudy",
            "date": "16 May 2016",
            "high": 61,
            "low": 47,
            "code": 28
          },
          {
            "day": "Tue",
            "text": "Scattered Showers",
            "date": "17 May 2016",
            "high": 62,
            "low": 51,
            "code": 39
          },
          {
            "day": "Wed",
            "text": "Scattered Showers",
            "date": "18 May 2016",
            "high": 66,
            "low": 50,
            "code": 39
          },
          {
            "day": "Thu",
            "text": "Mostly Cloudy",
            "date": "19 May 2016",
            "high": 71,
            "low": 51,
            "code": 28
          },
          {
            "day": "Fri",
            "text": "Showers",
            "date": "20 May 2016",
            "high": 73,
            "low": 58,
            "code": 11
          },
          {
            "day": "Sat",
            "text": "Scattered Thunderstorms",
            "date": "21 May 2016”,
            "high": 74,
            "low": 61,
            "code": 47
          },
          {
            "day": "Sun",
            "text": "Partly Cloudy",
            "date": "22 May 2016”,
            "high": 76,
            "low": 59,
            "code": 30
          },
          {
            "day": "Mon",
            "text": "Partly Cloudy",
            "date": "23 May 2016”,
            "high": 81,
            "low": 61,
            "code": 30
          },
          {
            "day": "Tue",
            "text": "Thunderstorms",
            "date": "24 May 2016",
            "high": 81,
            "low": 64,
            "code": 4
          },
          {
            "day": "Wed",
            "text": "Rain",
            "date": "25 May 2016",
            "high": 82,
            "low": 67,
            "code": 12
          }
        ],
        "lat": 37.030182,
        "guid": {
          "isPermaLink": false
        },
        "condition": {
          "text": "Cloudy",
          "date": "Mon, 16 May 2016 03:00 PM CDT",
          "temp": 60,
          "code": 26
        },
        "description": "<![CDATA[<img src=\"http://l.yimg.com/a/i/us/we/52/26.gif\"/>\n<BR />\n<b>Current Conditions:</b>\n<BR />Cloudy\n<BR />\n<BR />\n<b>Forecast:</b>\n<BR /> Mon - Mostly Cloudy. High: 61Low: 47\n<BR /> Tue - Scattered Showers. High: 62Low: 51\n<BR /> Wed - Scattered Showers. High: 66Low: 50\n<BR /> Thu - Mostly Cloudy. High: 71Low: 51\n<BR /> Fri - Showers. High: 73Low: 58\n<BR />\n<BR />\n<a href=\"http://us.rd.yahoo.com/dailynews/rss/weather/Country__Country/*https://weather.yahoo.com/country/state/city-12775789/\">Full Forecast at Yahoo! Weather</a>\n<BR />\n<BR />\n(provided by <a href=\"http://www.weather.com\" >The Weather Channel</a>)\n<BR />\n]]>",
        "link": "http://us.rd.yahoo.com/dailynews/rss/weather/Country__Country/*https://weather.yahoo.com/country/state/city-12775789/",
        "pubDate": "Mon, 16 May 2016 03:00 PM CDT",
        "long": -88.712601,
        "title": "Conditions for Paducah, KY, US at 03:00 PM CDT"
      },
      "image": {
        "link": "http://weather.yahoo.com",
        "height": 18,
        "url": "http://l.yimg.com/a/i/brand/purplelogo//uh/us/news-wea.gif",
        "width": 142,
        "title": "Yahoo! Weather"
      },
      "ttl": 60,
      "atmosphere": {
        "visibility": 16.1,
        "humidity": 60,
        "pressure": 1007,
        "rising": 0
      },
      "location": {
        "country": "United States",
        "city": "Paducah",
        "region": " KY"
      },
      "link": "http://us.rd.yahoo.com/dailynews/rss/weather/Country__Country/*https://weather.yahoo.com/country/state/city-12775789/",
      "lastBuildDate": "Mon, 16 May 2016 04:35 PM CDT",
      "wind": {
        "direction": 105,
        "chill": 59,
        "speed": 7
      },
      "title": "Yahoo! Weather - Paducah, KY, US"
    }
  ]
}

Answer 1

假设您正在询问如何从JSON中提取数据......

如果您使用节点控制台，您可以深入了解它并查看内部工作方式。

首先，将json数据分配给变量，即

var test = {
  "success": true,
  "data": [
    {
      "units": {
        "distance": "mi",
        "speed": "mph",
        "pressure": "in",
        "temperature": "F"
      },
      "language": "en-us", etc....

然后开始使用console.log挖掘数据：

> console.log(test);
{ success: true,
  data: 
  [ { units: [Object],
       language: 'en-us',
       description: 'Yahoo! Weather for Paducah, KY, US',

那么，我们如何获得成功＆＃34;？这很有效：

> console.log(test['success']);
true

但还有更好的方法：

> console.log(test.success);
true

现在，我们如何获得＆＃34;数据＆＃34;属性？

> console.log(test.data);
[ { units: { distance: 'mi', speed: 'mph', pressure: 'in', temperature: 'F' },
    language: 'en-us',
    description: 'Yahoo! Weather for Paducah, KY, US',
    astronomy: { sunrise: '5:45 am', sunset: '7:57 pm' },
    item: 
     { forecast: [Object],
       lat: 37.030182,

我们可以试试这个：

> console.log(test.data.units);
undefined

呃，哦......发生了什么事？简短回答，data是一个数组（[）

> console.log(test.data[0].units);
{ distance: 'mi', speed: 'mph', pressure: 'in', temperature: 'F' }

让我们再来一次：

> console.log(test.data[0].units.speed);
mph

使用此方法，您可以从JSON中提取任何信息。

从JSON文件返回特定数据

1 个答案: