Question

I would love some help with a regular expression that tests a string for a few things.

I need the user to enter a value that is at least 10 characters in length, contains at least 1 number, at least 1 special character, and at least 1 upper case letter.

Any help would be greatly appreciated.

Thanks!

Answer 1

Just have a separate regex for each of the constraints:

• at least 10 characters in length: .{10,},
• contains at least 1 number: [0-9],
• at least 1 special character: [^0-9a-zA-Z]
• at least 1 upper case letter: [A-Z]

And make sure that the string matches all of these regexes.

If you really need it, you can combine them all in one regex, using lookahead assertions:
(?=.*[0-9])(?=.*[^0-9a-zA-Z])(?=.*[A-Z]).{10,}