(to edit an existing user-defined
function) or the new function icon 
(to add
a new user-defined function).
Access this form by selecting the Functions node (within a database) in the
navigation pane and clicking
the design icon (to edit an existing user-defined
function) or the new function icon (to add
a new user-defined function).
Database Objects
Provides a list of database tables, columns, views etc which you can drag and drop
into the text area.
Keywords
Provides a list of common SQL commands which you can drag and drop into the text
area.
Name
View the name of the user-defined function.
Owner
View the owner of the user-defined function.
Use quoted identifiers
Specify if the function should allow quoted identifiers.
Text
View the syntax of the user-defined function.
Check Syntax
Check the syntax of the Transact-SQL script used to create the user-defined function.