Block E from being typed

Question

https://code.sololearn.com/We1rSdjApTeH/#html

Ok, so right now, I have this set to simply say "Invalid input" if an E is present.
But is there a way I can block E from being typed?
Maybe remove E from the array so it wont be evaluated?

UPDATE:
Corrected the title
Was: Block E from being typing?
Corrected to:
Block E from being typed?

I can engrish I swear

Answer 1

Add:

onkeydown="javascript: return event.keyCode == 69 ? false : true"

to your <input> tag in the HTML