javascript - Trying create a translator based on a preset alphabet -

ok, after looking @ several different things, i'm unsure how proceed trying create simple translator.

the translator use alphabet define user input pass through , convert. it's text binary format, except i'm defining stands each letter.

for example: = z, b = t, c = f, (etc).

for i'm not sure if should make object , use hasownproperty

like this: example

or if should make array , use loop.

if advise on best course, i'd grateful.