Appending a value from one field to another

[randle]

Hi

I have a form which has a field called "txtImageName" with a default value which will be a UNC path to a network folder.

I want to append to this path a value that is entered in another field called "Username". How do I go about doing this?

Also I'd like to be able to hide the network path from view, showing only the filename in the "txtImageName" field if possible.

Cheers