dynamic nested object loop js

Question

here is a json object i want to loop through:

{
  node: 'tree',
 text: 'Main Node',
  childs:[
      {
        node: 'tree',
        text: 'First Child',
        childs:[{
                node: 'tree',
                text: 'first child child'
               }....]
      },{
        node: 'tree',
        text: '2nd Child',
        childs:[{
                node: 'tree',
                text: '2nd child child'
               }...]
      }...]
}

here is the first type of json. but the problem is that json is dynamic and the child element vary depend upon different conditions. so i want to loop through the json and add leaf: true to the end of the last nested element. here is what is want:

{
      node: 'tree',
     text: 'Main Node',
      childs:[
          {
            node: 'tree',
            text: 'First Child',
            childs:[{
                    node: 'tree',
                    text: 'first child child',
                    leaf: true // i want to add this node to every last one
                   }]
          },{
            node: 'tree',
            text: '2nd Child',
            childs:[{
                    node: 'tree',
                    text: '2nd child child',
                    leaf: true
                   }]
          }]
    }

Does [this answer](https://stackoverflow.com/a/15268692/6836963) from another question help? — TheOdd, Sep 28 '17 at 18:33
no, because my json object nested element is not known. it can be nested upto 10 stages. and i don't know the stages in advance. — Waqar Haider, Sep 28 '17 at 18:35
Can't you just check for object key existence? Like `hasOwnProperty`? — TheOdd, Sep 28 '17 at 18:36

score 1 · Accepted Answer · answered Sep 28 '17 at 18:45

You can do it with a recursive function:

let objt = {
    node: 'tree',
    text: 'Main Node',
    childs: [
        {
            node: 'tree',
            text: 'First Child',
            childs: [{
                node: 'tree',
                text: 'Main Node'
            }]
        }, {
            node: 'tree',
            text: '2nd Child',
            childs: [{
                node: 'tree',
                text: '2nd child child'
            }]
        }]
};


function setLeaf(objt) {
    if (!objt.childs) {
        objt.leaf = true;
    } else {
        objt.childs.forEach(child => setLeaf(child))
    }
}

setLeaf(objt);

dynamic nested object loop js

1 Answers1