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

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)