How to Remove Whitespace using page composer

Summary:

Currently our suppliers us isupplier portal to send ASN (Advance Shipment Notic) informatoin, Since entering the Shipment number is a free text box input field sometime suppliers enters the shipment number with white space either at the begining or end of the shipment number. We really want that white space to be trim out from left and right bothe side while submitting the shipment number from isupplier portal.

Can you please confirm how we can achive this by page composer or if you know about any Expression lanugage which we can use for ltrim or Rtrim?