Regex for a random set of chars and digits

Question

I am looking for a regex that matches only when it sees a string that is randomly filled by digits and chars.

For example, adfak332arg3 is allowed but 332352 and fagaaah are not allowed. .*[^\\s] looks fine for strings with only chars but how to fix it to accepts the desired strings and refuses the other two types?

Answer 1

Use a positive lookahead (?=) to ensure that the string contains required characters.

^(?=.*[a-zA-Z])(?=.*\d)[a-zA-Z\d]+$

Test this regex pattern here.