Regex validation on decimal

Question

I am using the following regex to validate decimal numbers with dot .

/^[0-9]*\\.?[0-9]*$/

It works fine for all the cases except

Answer 1

Simply add one or more quantificator:

^[0-9]+(\.[0-9]+)?$

Answer 2

You can use this regex:

/^\d+(\.\d+)?$/

It will match whole number: 12, 1222

If there is a decimal point, then there must be at least 1 digit before and after the decimal point: 1.1, 34.2

These cases are not allowed: .43, 23.