with javascript, how to make string only have letters, numbers, and period. Remove all other characters

Question

What to edit in the js below, so this file name: old_file_name = this8_ file-name=44.jpg
becomes this: new_file_name = this8filename44.jpg

Replace any character unless it is a letter, number, or . with '' (ie. nothing)

var old_file_name = file.upload.filename;
new_file_name = old_file_name.replace(/^[ A-Za-z0-9.\s]*$/i, '');
console.log("file name is:"+new_file_name);
console.log("original file name is:"+old_file_name);

Answer 1

simply this :

const cleanFileName = fn => fn.replace(/[^a-z0-9.]/ig, '')
  ;
let old_file_name = "this8_ file-Name=44.jpg"
  , new_file_name = cleanFileName( old_file_name )
  ;
console.log( old_file_name )  // -> this8_ file-Name=44.jpg
console.log( new_file_name )  // -> this8fileName44.jpg

Answer 2

new_file_name = old_file_name.replace(^[A-Za-z0-9_.]+$, '');

This will check from start to finish if it matched one or more of the conditions.