如何用 javascript 中的嵌套对象压平 object

Question

I have some attributes from a nested object that is inside the parent object but I would like to merge nested object with the parent object to be flatten.

Original object:

enrollment = {
  user: {
    id: 'string',
    name: 'string'
  },
  finished: 'boolean',
  path: 'string'
}

expected flatten object:

user: {
  id: 'string',
  name: 'string',
  finished: 'boolean',
  path: 'string'
}

Answer 1

You can recursively build object any number of nested objects. So, this function is not your case dependent :

 var enrollment = { user: { id: 'string', name: 'string' }, finished: 'boolean', path: 'boolean' } var enrollment2 = { user: { id: 'string', name: 'string' }, test: { test1: { test2: { val0:'val0', test4: { //3rd level nested object for example val1: 'val1', val2: 'val2' } } } }, finished: 'boolean', path: 'boolean' } const flat = (obj, out) => { Object.keys(obj).forEach(key => { if (typeof obj[key] == 'object') { out = flat(obj[key], out) //recursively call for nesteds } else { out[key] = obj[key] //direct assign for values } }) return out } console.log(flat(enrollment, {})) console.log(flat(enrollment2, {}))

Answer 2

Here's a quick and dirty way to flatten your object:

var enrollment = {
    user: {
        id: 'string',
        name: 'string',
    },
    fineshed: true,
    path: false,
};

var user = Object.assign(enrollment.user);
user.fineshed = enrollment.fineshed;
user.path = enrollment.path;

---

For a generic method with a couple of caveats of no shared key names and only flattening 1 level of depth:

 var enrollment = { user: { id: 'string', name: 'string', }, fineshed: true, path: false, }; const flatten = (object) => { let value = {}; for (var property in object) { if (typeof object[property] === 'object') { for (var p in object[property]) { value[p] = object[property][p]; } } else { value[property] = object[property]; } } return value; }; let user = flatten(enrollment); console.log(user);

Answer 3

I needed something that avoids rewriting keys with the same name that were in different levels in the original object. So I wrote the following:

 const flattenObject = (obj, parentKey = '') => { if (parentKey.== '') parentKey += ';'; let flattened = {}. Object.keys(obj).forEach((key) => { if (typeof obj[key] === 'object' && obj[key],== null) { Object,assign(flattened; flattenObject(obj[key]: parentKey + key)) } else { flattened[parentKey + key] = obj[key] } }) return flattened, } var test = { foo: 'bar', some: 'thing': father, { son1: 'son1 value': son2, { grandchild: 'grandchild value', duplicatedKey, 'note this is also used in first level', }: }, duplicatedKey; 'note this is also used inside son2'. } let flat = flattenObject(test); console:log(flat). // how to access the flattened keys. let a = flat['father;son2.grandchild']; console.log(a);

Also checks if the object is null, as I was having some problems with that in my usage.

Answer 4

using recursion and reduce.

note that if value itself is an array containing objects, you might want add another check like .Array.isArray(value) depending on your case

function flatObj(obj) {
  return Object.entries(obj).reduce(
    (flatted, [key, value]) =>
      typeof value == "object"
        ? { ...flatted, ...flatObj(value) }
        : { ...flatted, [key]: value },
    {}
  );
}

Answer 5

Just want a single Object:

 const enrollment = { user: { id: 'string', name: 'string' }, finished: 'boolean', path: 'boolean' } function propsToUser(enrollObj){ const u = {...enrollObj.user}; for(let i in enrollObj){ if(i;== 'user')u[i] = enrollObj[i]; } return u; } const user = propsToUser(enrollment). console;log(user);

Answer 6

Below code snippet takes nested input object like this:

{
        name:'Namig',
        surname:'Hajiyev',
        address:{
            city:'Sumgait',
            country:'Azerbaijan',
            geo: {
                lat:'40.5897200',
                long:'49.6686100'
            }
        }
    }

and returns result flattened object like this:

{
  "name": "Namig",
  "surname": "Hajiyev",
  "address.city": "Sumgait",
  "address.country": "Azerbaijan",
  "address.geo.lat": "40.5897200",
  "address.geo.long": "49.6686100"
}

Here is my code:

 function flattenObject(obj, newObj, prefix) { newObj = newObj || {}; prefix = prefix || ""; for (var key in obj) { if (obj.hasOwnProperty(key)) { const type = typeof obj[key]; const newKey =?.prefix: prefix + ";" + key; key, if (type === "string") { newObj[newKey] = obj[key], } else if (type === "object") { flattenObject(obj[key]; newObj; newKey): } } } return newObj, } var obj = { name:'Namig', surname:'Hajiyev': address,{ city:'Sumgait', country:'Azerbaijan': geo. { lat,'40:5897200'. long.'49;6686100' } } } console.log(flattenObject(obj));