How can I remove all characters from a string that are not letters using a JavaScript RegEx?
You can use the replace method:
'Hey! The #123 sure is fun!'.replace(/[^A-Za-z]+/g, '');
>>> "HeyThesureisfun"
If you wanted to keep spaces:
'Hey! The #123 sure is fun!'.replace(/[^A-Za-z\s]+/g, '');
>>> "Hey The sure is fun"
The regex /[^a-z\s]/gi is basically saying to match anything not the letter a-z or a space (\s), while doing this globally (the g flag) and ignoring the case of the string (the i flag).