The reason that appendChild
is not a function is because you're executing it on the textContent
of your p
element.
You instead just need to select the paragraph itself, and then append your new text node to that:
var paragraph = document.getElementById("p");_x000D_
var text = document.createTextNode("This just got added");_x000D_
_x000D_
paragraph.appendChild(text);
_x000D_
<p id="p">This is some text</p>
_x000D_
However instead, if you like, you can just modify the text itself (rather than adding a new node):
var paragraph = document.getElementById("p");_x000D_
_x000D_
paragraph.textContent += "This just got added";
_x000D_
<p id="p">This is some text</p>
_x000D_