JavaScript: How to create unordered list from array?

I have the following array and I want to create an unordered list from it, but I am having trouble generating the unordered list in the proper format. I have searched similar questions but none of the existing solutions work for my problem.

var myArray = ['Value 1', ['Inner value 1', 'Inner value 2', 'Inner value 3', 'Inner value 4'], 'Value 2', 'Value 3', 'Value 4', 'Value 5', 'Value 6'];

Here is my JavaScript code:

function arrToUl(arr) {
  var div = document.getElementById('myList');
  var ul = document.createElement('ul');

  for (var i = 0; i < arr.length; i++) {

    if (arr[i] instanceof Array) {
      var list = arrToUl(arr[i]);
    } else {
      var li = document.createElement('li');
      li.appendChild(document.createTextNode(arr[i]));
      console.log(ul.appendChild(li));
    }
    div.appendChild(ul);
  }
}

arrToUl(myArray);

The above code is producing the following result:

<ul>
<li>Value 1</li>
<li>Inner Value 1</li>
<li>Inner Value 2</li>
<li>Inner Value 3</li>
<li>Inner Value 4</li>
<li>Value 2</li>
<li>Value 3</li>
<li>Value 4</li >
<li>Value 5</li >
<li>Value 6</li>

But the result should look like below:

<ul>
<li>Value 1
    <ul>
        <li>Inner Value 1</li>
        <li>Inner Value 2</li>
        <li>Inner Value 3</li>
        <li>Inner Value 4</li>
    </ul>
</li>
<li>Value 2</li>
<li>Value 3</li>
<li>Value 4</li>
<li>Value 5</li>
<li>Value 6</li>

Thank you for your help.

Answer

You’ve appended all the <ul> elements to the myList <div>. To change that, I’ve added a new parameter to the arrToUl(root, arr) function.

The new parameter, root, determines who the created <ul> should be appended to, so if the function encounters a sub-array, it uses the previous list item as the root for the creation of the sub-list.

var myArray = ['Value 1', ['Inner value 1', 'Inner value 2', 'Inner value 3', 'Inner value 4'], 'Value 2', 'Value 3', 'Value 4', 'Value 5', 'Value 6'];

function arrToUl(root, arr) {
  var ul = document.createElement('ul');
  var li;
  
  root.appendChild(ul); // append the created ul to the root

  arr.forEach(function(item) {
    if (Array.isArray(item)) { // if it's an array
      arrToUl(li, item); // call arrToUl with the li as the root
      return;
    }
    
    li = document.createElement('li'); // create a new list item
    li.appendChild(document.createTextNode(item)); // append the text to the li
    ul.appendChild(li); // append the list item to the ul
  });
}

var div = document.getElementById('myList');

arrToUl(div, myArray);

<div id="myList"></div>

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Answer