How validate decimal with optional percentage symbol using Regex?

问题

As the title of the question, I need to validate regex using the following values​​: (Maximum 2 decimal places, and 9 integers) with an optional percent symbol.

Valid:

10%
 0%
 1111111.12%
 15.2%
 10
 2.3

Invalid:

 .%
 12.%
 .02%
 %
 123456789123.123

I tryed:

^[0-9]{0,9}([\.][0-9]{0,2})\d[\%]{0,1}?$

But It does not work as I want.

回答1:

try this

^\d{1,9}(\.\d{1,2})?%?$

I tested over rubular and it is ok for your set of example.

回答2:

Try this:

^[0-9]{1,9}([\.][0-9]{1,2})?[\%]?$

来源：https://stackoverflow.com/questions/10560107/how-validate-decimal-with-optional-percentage-symbol-using-regex