Vaadin: How to make a validator accept numbers and one decimal only

问题

I'm trying to validate a textfield to it's only numbers and one decimal, but the decimal keeps causing the validator to go off:

TextField tf = new TextField();
tf.addValidator(new RegexpValidator("^\\d+$", facilityId.getCaption() + "Only numbers and one decimal allowed.")); 

So I got the numbers to work, but how do I tell the validator that the "." is okay?

Note: Add-Ons are not an option.

回答1:

This regex should work

/^\d+\.\d$|^\d+$/

Breakdown

^ - start of line

\d+ - One or more digit

\. - Escaping a period otherwise it will match any character

\d$ - It ends with one digit after the decimal

| - Or

^\d+$ - It has any number of digits without a decimal

来源：https://stackoverflow.com/questions/34054129/vaadin-how-to-make-a-validator-accept-numbers-and-one-decimal-only