Question

I have a text input field and I want to check what users put in there. I want to allow them to put a monetary amount with or with out $. They should be able to enter:

$12
$12.0
12
12.0
$ 12.0

not sure how would I do that. I think regex may help, but I’m not sure how to do that.

Answer 1

Basic regular expression.

(/^\$?\s?\d+(\.\d+)?$/).test("$12.0");


/ -Beginning of Reg Exp
^ - Start of line
\$? - Match a $ or not
\s? - Match a space or not
\d+ - match one or more numbers
(\.\d+)? - match a decimal point followed by more numbers
$ - match end of a line
/ - end of reg expression

This will fail

12. and .0

since they were not in your possible solutions