Finding object with specific value

Question

I have an tree structured object e.g

var x = [{
  id: 1,
  children: [{
    id: 11,
    children: [],
  }, {
    id: 12,
    children: [{
      id: 121,
      name:'jogn',
      children: []
    }]
  }]
}, {
  id: 2,
  children: [],
}]

And i would like to find object with specific ID in it. I made

function printObj(obj , val) {
  for( var i = 0; i < obj.length ; i++){
         if( obj[i].id == val){
         return obj[i];
         }
         if( obj[i].children.length > 0 ){
            printObj( obj[i].children)
         }
    }
}

function. The problem is when i invoke it

var g = printObj(x , 121);
alert(x.name)

it returns undefined instead of jogn altought when i pop some alert if it findes set value it does find it . Why is it returning wrong object then?

Also, you don't return anything from the printObj(children) so the recursive result will just disappear. — Shilly
– Shilly, Commented Jul 15, 2016 at 13:59

T.J. Crowder · Accepted Answer · 2016-07-15 13:57:17Z

Two problems with this line:

printObj( obj[i].children);

It's missing its second argument
You need to return its result if it finds one

So

var possibleResult = printObj( obj[i].children, val);
// -------------------------------------------^^^^^
if (possibleResult) {
    return possibleResult;
}

Separately, in your testing, you looked for x.name where you wanted g.name.

Fixed:

var x = [{
  id: 1,
  children: [{
    id: 11,
    children: [],
  }, {
    id: 12,
    children: [{
      id: 121,
      name: 'jogn',
      children: []
    }]
  }]
}, {
  id: 2,
  children: [],
}];

function printObj(obj, val) {
  for (var i = 0; i < obj.length; i++) {
    if (obj[i].id == val) {
      return obj[i];
    }
    if (obj[i].children.length > 0) {
      var possibleResult = printObj(obj[i].children, val);
      if (possibleResult) {
        return possibleResult;
      }

    }
  }
}

var g = printObj(x, 121);
console.log(g.name);

Bronson · Accepted Answer · 2016-07-15 15:11:35Z

0

Ramda is great for object and list work from functional approach - here is your data traversed -

    var x = [{
      id: 1,
      children: [{
        id: 11,
        children: [],
      }, {
        id: 12,
        children: [{
          id: 121,
          name: 'jogn',
          children: []
        }]
      }]
    }, {
      id: 2,
      children: [],
    }]


    const findById = (id, list) => map(o => {
      if(o.id === id) return o
      return findById(id, o.children)
    }, list)

    head(flatten(findById(121, x)))

answered Jul 15, 2016 at 15:11

Bronson

911 silver badge4 bronze badges

Collectives™ on Stack Overflow

Finding object with specific value

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related