javascript - 如何在控制台中打印来自世界银行的 JSOP 数据集的值？

Question

如何在控制台中打印控制台中 JSOP 对象的值。当我尝试使用 var countries = data.name 检索国家名称时，在控制台中打印未定义。我注意到 JSONP 对象中的标签是数字。我想知道我是否必须使用这些数字编写路线，但是当我尝试这样做时，它也不起作用。

var Getdata = function(data) {
console.log(data)

var countries = data.name;
console.log(countries)

}

var url = 'http://api.worldbank.org/countries/all/indicators/DT.DOD.PVLX.CD?date=2015&format=jsonp&prefix=Getdata';

var query_url = url;
console.log(query_url);

var script = document.createElement('script');
script.src = query_url;
document.getElementsByTagName('head')[0].appendChild(script);
</script>

Answer 1

查看数据，

[
    // this is data[0]
    {
        "page": 1,
        "pages": 6,
        "per_page": "50",
        "total": 264
    }, 
    // this is data[1]
    [
        // this is data[1][0]
        {
            "indicator": {
                "id": "DT.DOD.PVLX.CD",
                "value": "Present value of external debt (current US$)"
            },
            "country": {
                "id": "1A",
                "value": "Arab World"
            },
            "value": null,
            "decimal": "0",
            "date": "2015"
        }, 
        // data[1][1 ... 49] below here
        ... etc
    ]
] 

获取国家列表

var countries = data[1].map(function(item) {
    return item.country.value;
});

Of course, you're only getting a list of the first 50 countries in that result, you would need to call that API with some parameter to get the next 5 pages (you have page 1 of 6)

所以

http://api.worldbank.org/countries/all/indicators/DT.DOD.PVLX.CD?date=2015&format=jsonp&prefix=Getdata&page=2  
http://api.worldbank.org/countries/all/indicators/DT.DOD.PVLX.CD?date=2015&format=jsonp&prefix=Getdata&page=3
http://api.worldbank.org/countries/all/indicators/DT.DOD.PVLX.CD?date=2015&format=jsonp&prefix=Getdata&page=4
http://api.worldbank.org/countries/all/indicators/DT.DOD.PVLX.CD?date=2015&format=jsonp&prefix=Getdata&page=5
http://api.worldbank.org/countries/all/indicators/DT.DOD.PVLX.CD?date=2015&format=jsonp&prefix=Getdata&page=6

同样需要检索

这是一种检索所有国家/地区的方法

var Getdata = (function() {
    var url = 'http://api.worldbank.org/countries/all/indicators/DT.DOD.PVLX.CD?date=2015&format=jsonp&prefix=Getdata';
    var allCountries = [];
    var callback;

    return function Getdata(data) {
        var hdr,
            arr, 
            countries;
        if (typeof data == 'function') {
            // called by code
            callback = data; // setup the callback
            allCountries = [];
        } else {
            // called by JSONP type callback
            hdr = data[0];
            arr = data[1];

            countries = arr.map(function(item) {
                return item.country.value;
            });
            allCountries = allCountries.concat(countries);
        }
        if (!hdr || hdr.page < hdr.pages) {
            // get the first (hdr is undefined) or next page
            var script = document.createElement('script');
            script.src = url + (hdr ? '&page=' + (hdr.page + 1) : '');
            document.getElementsByTagName('head')[0].appendChild(script);
        } else {
            // done, callback the countries
            callback(allCountries);
        }
    };
})();

刚刚的电话

Getdata(function(data) {
    console.log(data);
});