flattening the nested object in javascript

Question

I ran into this problem, I was able to write solution which can handle array of object (not posted here) or one level deep nested object but i couldn\'t solve when the given

Answer 1

I am very late to the party but it can be easily achieved with a module like Flatify-obj.

Usage:

   const flattenObject = require('flatify-obj');

   flattenObject({foo: {bar: {unicorn: '                                                                    

                                                        
            

Answer 2

one more simple example with Object.keys

 const apple = { foo: { boo : { doo : 1 } } }


let newObj = {}
const format = (obj,str) => {
  Object.keys(obj).forEach((item)=>{
     if(typeof obj[item] ==='object'){
        const s = !!str? str+'.'+item:item
        format(obj[item],s)
     } else {
       const m = !!str?`${str}.`:''
       newObj[m+item]= obj[item]
     }
  })

}

format(apple,'')

console.log(newObj)

Answer 3

You should be able to do it fairly simply with recursion. The way it works, is you just recursively call a parser on object children that prepend the correct key along the way down. For example (not tested very hard though):

const source = {
  a: 1,
  b: {
    c: true,
    d: {
      e: 'foo'
    }
  },
  f: false,
  g: ['red', 'green', 'blue'],
  h: [{
    i: 2,
    j: 3
  }]
}

const flatten = (obj, prefix = '', res = {}) => 
  Object.entries(obj).reduce((r, [key, val]) => {
    const k = `${prefix}${key}`
    if(typeof val === 'object'){ 
      flatten(val, `${k}.`, r)
    } else {
      res[k] = val
    }
    return r
  }, res)
 
console.log(flatten(source))