Iterate nested array which is dynamically created

Question

I have an array of objects, each object MAY contain more arrays of objects and so on. I want to iterate through all these objects without hard coding it. I don't know how many nested arrays will each object have.

// This is the parent array
var members = [Object, Object, Object, Object, Object];

// members[0] can have another array of objects
var member = members[0];

and so on....
var mem = member[0];

I want to iterate through all those objects, but like I said, I can't know how many there will be. I need to get label of every object which I currently get by Object.label I hope I explained it well, here's the picture. Array[5] is var members in my example

So you loop over the array and read the label? And when you encounter the next object, you do recursion and loop over that. — epascarello
– epascarello, Commented Apr 11, 2017 at 12:45
You can use recursion. But this will need a standard object structure — Rajesh Dixit
– Rajesh Dixit, Commented Apr 11, 2017 at 12:45

zybreak · Accepted Answer · 2017-04-11 13:09:09Z

3

I would solve this with a recursive function that iterates through all children. Given they all share the same structure.

function visit(o) {
  for (var i = 0; i<o.length; i++) {        
    /* do something useful */
    console.log(o[i].label);

    if (Array.isArray(o[i].children)) {
      visit(o[i].children);
    }
  }
}

edited Apr 11, 2017 at 13:09

answered Apr 11, 2017 at 12:48

zybreak

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1 Comment

Dino Over a year ago

Got it working. your o in if should be with [ i ]. So if (o[i].children) { visit(o[i].children); }

Mosd · Accepted Answer · 2017-04-11 13:11:19Z

1

Another way:

function getMembers(list){
  list.forEach(function(item){
    console.log(item.label); 
    if(item.children){
      getMembers(item.children)
    }
  });
}

var members = [{label: 'label1', children:[{label: 'label21'}, {label: 'label22'}]}, {label: 'label2'}, {label: 'label3'}];

getMembers(members);

answered Apr 11, 2017 at 13:11

Mosd

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Comments

S B · Accepted Answer · 2017-04-11 12:59:36Z

0

Try this. Check whether child element is array using Js Array.isArray and if it is array call the function someFn again

function someFn(members) {
var labels=[]
for (var i = 0; i<members.length; i++) { 
    labels.push(members[i].label)

    if (Array.isArray(members[i]) && members[i].length>0) {
      someFn(members[i]);
    }
  }
retun labels;
}
var membersArray = [Object, Object, Object, Object, Object];
var labelsArray= someFn(membersArray);
console.log(labelsArray);

I'll add some demo later

answered Apr 11, 2017 at 12:59

S B

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Comments

Kinjal Akhani · Accepted Answer · 2017-04-11 13:14:23Z

0

    var jsonArr = [{"children":["New1","New2","New3","New4"]},{"children1":
                  ["New11","New12","New13","New14"],"children2":
                  ["New21","New22","New23","New24"]},{"children2":
                  ["New21","New22","New23","New24"]}];

	function callRecFunc(obj){
		$.each(obj,function(i,o){
			if(o != undefined && o instanceof Array){
				callRecFunc(o);
			}
			else{
				console.log(o);
			}
		});
	}

	$.each(jsonArr,function(ind,obj){
			callRecFunc(obj);
	})

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

answered Apr 11, 2017 at 13:14

Kinjal Akhani

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1 Comment

Kinjal Akhani Over a year ago

Try out this code, this recursion is work for all the nested arrays and after that it will print array element data. But at the leaf node there must be a simple array with values

cнŝdk · Accepted Answer · 2017-04-11 13:49:39Z

0

You can write a function that given an object it will read label property in this object and loop throught children array of this object if it exists.

function readObj(obj){
  console.log(obj.label);
  if(obj.children && obj.children.length>0){
       obj.children.map(readObj);
  }
}

And then apply this function to all members array.

function readObj(obj) {
  console.log(obj.label);
  if (obj.children && obj.children.length > 0) {
    obj.children.map(readObj);
  }
}

var members = [{
  label: "label1"
}, {
  label: "Label2",
  children: [{
    label: "child1"
  }, {
    label: "child2"
  }]
}, {
  label: "label3",
  children: [{
    label: "child3"
  }]
}];

members.map(readObj);

edited Apr 11, 2017 at 13:49

answered Apr 11, 2017 at 13:03

cнŝdk

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