需要一种在不遍历父对象的情况下从对象数组中随机拾取值的方法

Question

我对JavaScript还很陌生，需要帮助完成我正在尝试完成的任务。

我有一个像这样的对象数组：

const data =
{
"Total_packages": {
"package1": {
"tags": [
"kj21",
"j1",
"sj2",
"z1"
],
"expectedResponse": [
{
"firstName": "Name",
"lastName": "lastName",
"purchase": [
{
"title": "title",
"category": [
"a",
"b",
"c"
]
}
]
}
]
},
"package2": {
"tags": [
"s2",
"dsd3",
"mhg",
"sz7"
],
"expectedResponse": [
{
"firstName": "Name1",
"lastName": "lastName1",
"purchase": [
{
"title": "title1",
"category": [
"a1",
"b1",
"c1"
]
}
]
}
]
},
"package3": {
"tags": [
"s21",
"dsd31",
"mhg1",
"sz71"
],
"expectedResponse": [
{
"firstName": "Name2",
"lastName": "lastName2",
"purchase": [
{
"title": "title2",
"category": [
"a2",
"b2",
"c2"
]
}
]
}
]
},
"package4": {
"tags": [
"s22",
"dsd32",
"mhg2",
"sz72"
],
"expectedResponse": [
{
"firstName": "Name3",
"lastName": "lastName3",
"purchase": [
{
"title": "title3",
"category": [
"a3",
"b3",
"c3"
]
}
]
}
]
},
"package5": {
"tags": [
"s22",
"dsd32",
"mhg2",
"sz72"
],
"expectedResponse": [
{
"firstName": "Name4",
"lastName": "lastName4",
"purchase": [
{
"title": "title4",
"category": [
"a4",
"b4",
"c4"
]
}
]
}
]
}
}
}
var arrRand = genNum(data, 3);
console.log(arrRand);
function genNum(data, loop='') {
var list = [];
var arrayOfTags = Object.entries(data.Total_packages).reduce((acc, [k, v]) => {
if (v.tags) acc = acc.concat(v.tags.map(t => ({tag: t, response: v.expectedResponse})));
return acc;
}, []);
for (var i = 0; i < loop; i++){
var randomIndex = Math.floor(Math.random() * arrayOfTags.length);
var randomTag = arrayOfTags[randomIndex];
list.push(randomTag);
}
return list;
}

然后，我通过执行arrRand[0].tag和arrRand[0].response.之类的操作来访问我需要的值

通常情况下，我从以下方法中得到重复的响应，这就成了问题：

[
{
"tag": "s22",
"response": [
{
"firstName": "Name4",
"lastName": "lastName4",
"purchase": [
{
"title": "title4",
"category": [
"a4",
"b4",
"c4"
]
}
]
}
]
},
{
"tag": "dsd31",
"response": [
{
"firstName": "Name2",
"lastName": "lastName2",
"purchase": [
{
"title": "title2",
"category": [
"a2",
"b2",
"c2"
]
}
]
}
]
},
{
"tag": "dsd31",
"response": [
{
"firstName": "Name2",
"lastName": "lastName2",
"purchase": [
{
"title": "title2",
"category": [
"a2",
"b2",
"c2"
]
}
]
}
]
}
]

我的目标是发送API请求；标签"；值，然后将我从调用中得到的响应匹配到数据的expectedResponse部分。

我最初的想法是做一些类似的事情：

data.Total_packages.tags[Math.floor(Math.random() * data.Total_packages.tags.length)];

然而，我不能打电话给"标签"；而不遍历其父对象，即"0"；包装1"；或"；包装2"；，这样它就不再是随机的了。

我知道可能有一种非常简单的方法我没有得到。如有任何建议，我们将不胜感激。

Answer 1

您可以从各种标记元素构建一个数组，并使用它来执行随机操作。

const data =
{
"Total_packages": {
"package1": {
"tags": [
"kj21",
"j1",
"sj2",
"z1"
],
"expectedResponse": [
{
"firstName": "Name",
"lastName": "lastName",
"purchase": [
{
"title": "title",
"category": [
"a",
"b",
"c"
]
}
]
}
]
},
"package2": {
"tags": [
"s2",
"dsd3",
"mhg",
"sz7"
],
"expectedResponse": [
{
"firstName": "Name1",
"lastName": "lastName1",
"purchase": [
{
"title": "title1",
"category": [
"a1",
"b1",
"c1"
]
}
]
}
]
}
}
}
const arrayOfTags = Object.entries(data.Total_packages).reduce((acc, [k, v]) => {
if (v.tags) acc = acc.concat(v.tags.map(t => ({tag: t, response: v.expectedResponse})));
return acc;
}, []);
const randomIndex = Math.floor(Math.random() * arrayOfTags.length);
const randomTag = arrayOfTags[randomIndex];
console.log(randomTag.tag, randomTag.response);

Answer 2

您将需要挖掘标记，将它们放在一个数组中，并随机化索引，最终获得那里的值。下面的解决方案假设您的标签都是data.Total_packages[whateverpackage]内的阵列

const data =
{
"Total_packages": {
"package1": {
"tags": [
"kj21",
"j1",
"sj2",
"z1"
],
"expectedResponse": [
{
"firstName": "Name",
"lastName": "lastName",
"purchase": [
{
"title": "title",
"category": [
"a",
"b",
"c"
]
}
]
}
]
},
"package2": {
"tags": [
"s2",
"dsd3",
"mhg",
"sz7"
],
"expectedResponse": [
{
"firstName": "Name1",
"lastName": "lastName1",
"purchase": [
{
"title": "title1",
"category": [
"a1",
"b1",
"c1"
]
}
]
}
]
}
}
}
let tags = [];
for (let key in data.Total_packages) {
if (data.Total_packages[key].tags) tags = tags.concat(data.Total_packages[key].tags);
}
console.log(tags[parseInt(tags.length * Math.random())]);

编辑

在评论部分，你提到你有形式的副本

[
{
"tag": "s22",
"response": [
{
"firstName": "Name4",
"lastName": "lastName4",
"purchase": [
{
"title": "title4",
"category": [
"a4",
"b4",
"c4"
]
}
]
}
]
},
{
"tag": "dsd31",
"response": [
{
"firstName": "Name2",
"lastName": "lastName2",
"purchase": [
{
"title": "title2",
"category": [
"a2",
"b2",
"c2"
]
}
]
}
]
},
{
"tag": "dsd31",
"response": [
{
"firstName": "Name2",
"lastName": "lastName2",
"purchase": [
{
"title": "title2",
"category": [
"a2",
"b2",
"c2"
]
}
]
}
]
}
]

这就是如何消除重复：

let input = [
{
"tag": "s22",
"response": [
{
"firstName": "Name4",
"lastName": "lastName4",
"purchase": [
{
"title": "title4",
"category": [
"a4",
"b4",
"c4"
]
}
]
}
]
},
{
"tag": "dsd31",
"response": [
{
"firstName": "Name2",
"lastName": "lastName2",
"purchase": [
{
"title": "title2",
"category": [
"a2",
"b2",
"c2"
]
}
]
}
]
},
{
"tag": "dsd31",
"response": [
{
"firstName": "Name2",
"lastName": "lastName2",
"purchase": [
{
"title": "title2",
"category": [
"a2",
"b2",
"c2"
]
}
]
}
]
}
];
let output = input.filter((item, index) => {
return input.filter((item2, index2) => {
return ((item.tag === item2.tag) && (index2 < index));
}).length === 0;
});
console.log(output);

我们搜索在早期索引中没有匹配项的项目。

Answer 3

i将所有标签保存在一个单独的数组中，并在块中保留expectedResponse的ref。那么这是随机选择一个标签索引并与块预期响应索引匹配的问题。可能需要对随机/长度进行一些调整，但我希望它能让你朝着正确的方向前进。

var tags = []
var block = Object.values(data.Total_packages).flat()
block.forEach(item => tags = [...tags, ...item.tags])
var index = tags[parseInt(tags.length * Math.random())]
console.log(block[Math.floor(tags.indexOf(index) / 4)].expectedResponse)