AngularJS - Remove leading and trailing whitespace from input-box using regex

Question

I am writing a regular expression(regex) for adding multiple email ids in an input box with following conditions:

1. Multiple email ids must be separated with com

Answer 1

Do you want leading/trailing spaces allowed on the whole string, or around each individual address?

For the former your regex should be

/^(\s*([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5}){1,25})+([,.](([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5}){1,25})+\s*)*$/

and for the latter

/^(\s*([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5}){1,25}\s*)+([,.](\s*([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5}){1,25})+\s*)*$/