Question

我必须动态构建两种类型的数组。

data['fields']['title']

和

data['fields']['description']['html']

它返回此结构的内容：

{   
    "fields": {
        "title": "Headline",
        "description": {
            "html": "<p>description text</p>"
        }   
    },   
    "meta": {
        "id": "995915463198380032"   
    } 
}

问题是“动态地”。

我调用一个函数，并通过它给出路径，例如“ description>html”。我将字符串分为“描述”和“ html”。但是，现在我该如何构建数组：data['fields']['description']['html']

有时候，或多或少都有一个类似于“标题”的等级。如果我想称呼标题，则数组就像data['fields']['title']

所以数组的内容和数量是动态的。

我自己尝试过这个：

function comfort_x(item_fields) {


var splitter = item_fields.split(">");
var content = new Array();

for (var i = 1; i < splitter.length; ++i) {
    content['splitter['+i+']'] = splitter[i];
}

data['fields'][splitter[0]][splitter[1]];

}

谢谢您的帮助。

Answer 1

您可以创建一个函数来查找传递的级别。您可以split >的路径，并使用源输入来缩小该数组。

(data, path) => path.split(">").reduce((r, e) => r[e], data);

这里是一个例子。

var obj = {   
    "fields": {
        "title": "Headline",
        "description": {
            "html": "<p>description text</p>"
        }   
    },   
    "meta": {
        "id": "995915463198380032"   
    } 
}

var lookUp = (o, path) => path.split(">").reduce((r, e) => r[e], o);

console.log('fields: ', lookUp(obj, 'fields'))
console.log('fields>title: ', lookUp(obj, 'fields>title'))
console.log('fields>description>html: ', lookUp(obj, 'fields>description>html'))

Answer 2

它与以下其他解决方法一起工作：

        switch (splitter.length) {
        case 0:
            item.innerHTML = data['fields'];
        break;
        case 1:
           item.innerHTML = data['fields'][splitter[0]];
        break;
        case 2:
            item.innerHTML = data['fields'][splitter[0]][splitter[1]];
        break;
        case 3:
            item.innerHTML = data['fields'][splitter[0]][splitter[1]][splitter[2]];

    }

也许您有一个更聪明的解决方案。

Answer 3

/*
    Be careful! The function won’t return a new object, 
    but take a reference to the input object aka. alter 
    it and don’t deep-clone it.
*/
const myObject = {};

function setValueByKeypath(object, path, value, separator = ">") {
    path = path.split(separator);
    let currentPart = object;
    for (let i = 0, len = path.length; i < len; i++) {
        const key = path[i];
        const keyValue = (i === len - 1) ? value : {};
        if (typeof currentPart[key] === "undefined") {
            currentPart[key] = keyValue;
        }
        currentPart = currentPart[key];
    }       
}

setValueByKeypath(myObject, "fields>description>html", "<p>description text</p>");
console.log(myObject);

setValueByKeypath(myObject, "fields>title", "Headline");
console.log(myObject);

setValueByKeypath(myObject, "meta>id", "995915463198380032");
console.log(myObject);

如何获得深层嵌套对象的某些价值？

3 个答案: