Javascript - Append HTML to container element without innerHTML

I am surprised that none of the answers mentioned the insertAdjacentHTML() method. Check it out here. The first parameter is where you want the string appended and takes ("beforebegin", "afterbegin", "beforeend", "afterend"). In the OP's situation you would use "beforeend". The second parameter is just the html string.

Basic usage:

var d1 = document.getElementById('one');
d1.insertAdjacentHTML('beforeend', '<div id="two">two</div>');

To give an alternative (as using DocumentFragment does not seem to work): You can simulate it by iterating over the children of the newly generated node and only append those.

var e = document.createElement('div');
e.innerHTML = htmldata;

while(e.firstChild) {
    element.appendChild(e.firstChild);
}

alnafie has a great answer for this question. I wanted to give an example of his code for reference:

var childNumber = 3;

function addChild() {
  var parent = document.getElementById('i-want-more-children');
  var newChild = '<p>Child ' + childNumber + '</p>';
  parent.insertAdjacentHTML('beforeend', newChild);
  childNumber++;
}

body {
  text-align: center;
}
button {
  background: rgba(7, 99, 53, .1);
  border: 3px solid rgba(7, 99, 53, 1);
  border-radius: 5px;
  color: rgba(7, 99, 53, 1);
  cursor: pointer;
  line-height: 40px;
  font-size: 30px;
  outline: none;
  padding: 0 20px;
  transition: all .3s;
}
button:hover {
  background: rgba(7, 99, 53, 1);
  color: rgba(255,255,255,1);
}
p {
  font-size: 20px;
  font-weight: bold;
}

<button type="button" onclick="addChild()">Append Child</button>
<div id="i-want-more-children">
  <p>Child 1</p>
  <p>Child 2</p>
</div>

Hopefully this is helpful to others.