Question

I need a regex which will satisfy both conditions.

It should give me true only when a String contains both A-Z and 0-9.

Here’s what I’ve tried:

if PNo[0].matches("^[A-Z0-9]+$")

It does not work.

Answer 1

I suspect that the regex below is slowed down by the look-around, but it should work regardless:

.matches("^(?=.*[A-Z])(?=.*[0-9])[A-Z0-9]+$")

The regex asserts that there is an uppercase alphabetical character (?=.*[A-Z]) somewhere in the string, and asserts that there is a digit (?=.*[0-9]) somewhere in the string, and then it checks whether everything is either alphabetical character or digit.