Yes, there are two ways to go about achieving this.
1) on your dynamic forms page, let's say you have a shortname field called "CreditCardNumber", along with other fields. When you edit the "CreditCardNumber", you can go to Advance Field Options and check the box for "Encrypt / decrypt field results". However, by using this option, the only way to view the result is to use Dynamic Forms built in "View Form Results". You can configure "View Form Results" to be viewable only to Administrators of the website under "Module Configuration / View Results Option Security"
2) or you can create your own SQL table (
http://dotnetslackers.com/articles/...rial.aspx) with the CreditCardNumber column as an encrypted column and use an SQL completion event (calling a stored procedure) in Dynamic Forms to insert the data into this SQL table. With this method, an admin with access to Host / SQL in DNN or SQL Management Studio can query directly against the SQL table to retrieve the CreditCardNumber (unencrypted SQL query obviously). -- David