# Extra Functionality ## Hidden fields removed If any fields on the form are hidden fields they will be removed. *(With the exception of the "emailsubjectprefix" field.)* If hidden data needs to be passed back to the server via the form a textbox should be used and hidden with css. ## emailsubjectprefix If there is a field call "emailsubjectprefix" in the form, then the value of that fields will be taken as a prefix to the email subject. *Example Tempate Code* ``` @HiddenField(new SimplisityInfo(), "genxml/hidden/emailsubjectprefix","","DefaultPREFIX") ``` ``` @TextBox(new SimplisityInfo(), "genxml/textbox/emailsubjectprefix", " class='w3-input w3-border'") ``` The idea is that the value of the field can be altered based on selections the user makes in the form. NOTE: Ensure the field is within the s-return element.