RegEx for Javascript to allow only alphanumeric

Question

I need to find a reg ex that only allows alphanumeric. So far, everyone I try only works if the string is alphanumeric, meaning contains both a letter and a number. I just w

Answer 1

It seems like many users have noticed this these regular expressions will almost certainly fail unless we are strictly working in English. But I think there is an easy way forward that would not be so limited.

1. make a copy of your string in all UPPERCASE
2. make a second copy in all lowercase

Any characters that match in those strings are definitely not alphabetic in nature.

let copy1 = originalString.toUpperCase();
let copy2 = originalString.toLowerCase();
for(let i=0; i

Optionally, you can also detect numerics by just looking for digits 0 to 9.