I want to check if a file that I don't know part of the file name exists or not in javascript. what should I do? it's possible?

the file name must be something like this :

kdo-! Something-234555124427609834.txt

I tried to do like this :

var matches = text.match(/ejx-[\s\S]*-theCode/);

but theCode is a variable and I don't know what should I do more. it doesn't work