Access to an object value from array of keys

October 19, 2022

I have a object like this:

const obj = {
A:{ 
  a1:'vala1', 
  a2:'vala2'
},
B:{
  b1: 'valb1',
  b2: 'valb2'
},
C:{
  c1:{
    c11:'valc11'
  },
  c2:'valc2'
}
}

An array like this const ar = [‘C’,’c1′,’c11′];

How can I get the value identify by concatenation of my array keys? (obj.C.c1.c11)

>Solution :

You can use the following function and pass an object and an array of keys in order to get the corresponding value:

const obj = {
  A:{ 
    a1:'vala1', 
    a2:'vala2'
  },
  B:{
    b1: 'valb1',
    b2: 'valb2'
  },
  C:{
    c1:{
      c11:'valc11'
    },
    c2:'valc2'
  }
}

const arr: string[] = ['C','c1','c11'];

function getVal(obj, arr: string[]) {
  if ( arr.length === 1 ) {
    return obj[arr[0]];   
  }
  return getVal(obj[arr[0]], arr.slice(1));
}

console.log(getVal(obj, arr));