javascript - NodeJS - 从多级对象数组中提取数据

Question

我有以下 JSON 数组:

{
"list": [{
    "name": "Assignment",
    "id": 67,
    "template": 0,
    "children": [{
        "assignmentnumber": 1000,
        "fromCountry": "Sweden",
        "toCountry": "Spain",
        "fromCity": "Stockholm",
        "toCity": "Madrid"
    }, {
        "assignmentnumber": 15678,
        "fromCountry": "Sweden",
        "toCountry": "Germany",
        "fromCity": "Stockholm",
        "toCity": "Berlin"
    }, {
        "assignmentnumber": 10001,
        "fromCountry": "Sweden",
        "toCountry": "United Kingdom",
        "fromCity": "Stockholm",
        "toCity": "London"
    }]
}, {
    "name": "Valuation form",
    "id": 36,
    "template": 0,
    "children": [15678]
}, {
    "name": "Claim",
    "id": 12,
    "template": 0,
    "children": [1000, 10001]
}]
}

我需要从仅包含“name”元素的数组中提取一个新数组。我尝试过 lodash，但不知道如何正确使用它。

谁能告诉我如何做到这一点？

Answer 1

您应该使用map方法，该方法接受callback函数作为参数。

The map() method creates a new array with the results of calling a provided function on every element in this array.

var array=obj.list.map(callback);
function callback(item){
    return item.name;
}

或者简单地说:

var array=obj.list.map(el=>el.name);

var obj={
"list": [{
    "name": "Assignment",
    "id": 67,
    "template": 0,
    "children": [{
        "assignmentnumber": 1000,
        "fromCountry": "Sweden",
        "toCountry": "Spain",
        "fromCity": "Stockholm",
        "toCity": "Madrid"
    }, {
        "assignmentnumber": 15678,
        "fromCountry": "Sweden",
        "toCountry": "Germany",
        "fromCity": "Stockholm",
        "toCity": "Berlin"
    }, {
        "assignmentnumber": 10001,
        "fromCountry": "Sweden",
        "toCountry": "United Kingdom",
        "fromCity": "Stockholm",
        "toCity": "London"
    }]
}, {
    "name": "Valuation form",
    "id": 36,
    "template": 0,
    "children": [15678]
}, {
    "name": "Claim",
    "id": 12,
    "template": 0,
    "children": [1000, 10001]
}]
};
console.log(obj.list.map(function(item){
    return item.name;
}));