I love the way you check for invalid characters and the "field" keyword in your
code. There is one minor thing to correct if you don't want the user to use the
field keyword at all: at the moment you perform a case sensitive test for
"field", so the user could enter "Field" or "FIELD" (Domino doesn't care). To
make your test case sensitive just change the line declaring the first regular
var regExp1 = /\bfield\b/i
(added the i at the end for ignore case). That's it.