JQuery从JSON数组中获取数据

Question

这是我从foursquare获得的JSON的一部分.

JSON

tips: {
    count: 2,
    groups: [
    {
        type: "others",
        name: "Tips from others",
        count: 2,
        items: [
        {
            id: "4e53cf1e7d8b8e9188e20f00",
            createdAt: 1314115358,
            text: "najja?i fitness centar u gradu",
            canonicalUrl: "https://foursquare.com/item/4e53cf1e7d8b8e9188e20f00",
            likes: {
                count: 2,
                groups: [
                {
                    type: "others",
                    count: 2,
                    items: []
                }],
                summary: "2 likes"
            },
            like: false,
            logView: true,
            todo: {
                count: 0
            },
            user: {
                id: "12855147",
                firstName: "Damir",
                lastName: "P.",
                gender: "male",
                photo: {
                    prefix: "https://irs1.4sqi.net/img/user/",
                    suffix: "/AYJWDN42LMGGD2QE.jpg"
                }
            }
        },
        {
            id: "4e549e39152098912f227203",
            createdAt: 1314168377,
            text: "ajd da vidimo hocu li znati ponoviti",
            canonicalUrl: "https://foursquare.com/item/4e549e39152098912f227203",
            likes: {
                count: 0,
                groups: []
            },
            like: false,
            logView: true,
            todo: {
                count: 0
            },
            user: {
                id: "12855147",
                firstName: "Damir",
                lastName: "P.",
                gender: "male",
                photo: {
                    prefix: "https://irs1.4sqi.net/img/user/",
                    suffix: "/AYJWDN42LMGGD2QE.jpg"
                }
            }
        }]
    }]
}

我需要获取最后一个提示文本,编写它的用户以及撰写/发布它的日期.

用户:Damir P.

日期:1314115358

文字:najjači健身中心你毕业

我尝试使用JQuery,这可以获取非数组值:

$.getJSON(url, function(data){
    var text= data.response.venue.tips.groups.items.text;
    alert(text);
});

但它不适用于数组.

结果:未捕获的TypeError:无法读取未定义的属性"text".

我也试过$ .each,但没有效果.

$.getJSON(url, function(data){
    $.each(data.response.venue.tips.groups.items.text, function (index, value) {
        console.log(value);
    });
});

我究竟做错了什么 ？

Answer 1

您需要迭代组和项目.$ .each()将一个集合作为第一个参数,并data.response.venue.tips.groups.items.text 尝试指向一个字符串.这两个groups和items是数组.

详细版本:

$.getJSON(url, function (data) {

    // Iterate the groups first.
    $.each(data.response.venue.tips.groups, function (index, value) {

        // Get the items
        var items = this.items; // Here 'this' points to a 'group' in 'groups'

        // Iterate through items.
        $.each(items, function () {
            console.log(this.text); // Here 'this' points to an 'item' in 'items'
        });
    });
});

或者更简单:

$.getJSON(url, function (data) {
    $.each(data.response.venue.tips.groups, function (index, value) {
        $.each(this.items, function () {
            console.log(this.text);
        });
    });
});

在您指定的JSON中,最后一个是:

$.getJSON(url, function (data) {
    // Get the 'items' from the first group.
    var items = data.response.venue.tips.groups[0].items;

    // Find the last index and the last item.
    var lastIndex = items.length - 1;
    var lastItem = items[lastIndex];

    console.log("User: " + lastItem.user.firstName + " " + lastItem.user.lastName);
    console.log("Date: " + lastItem.createdAt);
    console.log("Text: " + lastItem.text);
});

这会给你:

用户:Damir P.
日期:1314168377
文字:ajd da vidimo hocu li znati ponoviti

Answer 2

你没有循环遍历这些项目.试试这个:

$.getJSON(url, function(data){
    $.each(data.response.venue.tips.groups.items, function (index, value) {
        console.log(this.text);
    });
});