Can Alter (current) Database?

I have a *.sql script that creates database tables, and I need to modify the database to enable the service broker. In addition, the actual name of the database is not known in advance - it is set per instance of the application.

I know I need to do:

ALTER DATABASE dbname SET ENABLE_BROKER

But I must avoid including the name of the database in the script. I did wonder if this would work:

DECLARE @DB varchar(50)

SELECT @DB = DB_NAME()

ALTER DATABASE @DB SET ENABLE_BROKER

But I just get a syntax error. Presumably this also rules out setting the database name as a parameter to the script (SqlParameter stuff)

The only option I can think of is dynamically creating the statement, either in T-SQL or in the calling .NET environment.

Any thoughts?

Ruth