Regular expression that allows spaces in a string, but not only blank spaces

Question

I need to write a regular expression for form validation that allows spaces within a string, but doesn\'t allow only white space.

For example - \'Chicago Heigh

Answer 1

If we wanted to apply validations only with allowed character set then I tried with USERNAME_REGEX = /^(?:\s*[.\-_]*[a-zA-Z0-9]{1,}[.\-_]*\s*)$/;

• A string can contain any number of spaces at the beginning or ending or in between but will contain at least one alphanumeric character.
• Optional ., _ , - characters are also allowed but string must have one alphanumeric character.