Hello Font,

According to
http://msdn2.microsoft.com/en-us/vstudio/aa700921.aspx you can't do that

Just create a normal assembly and mark the (static) method with the
SqlProcedure attribute:

public class SPClass
{
[Microsoft.SqlServer.Server.SqlProcedure]
public static void Foo()

then import into sql server using sql (using create assembly from and
create proceure external_name

like

create assembly [assemblyname] from 'x:\SPClass.dll' with permission_set
= safe (or whatever permission set you want)

create procedure [procname]
as external name [assemblyname][classname]

Run the sql script as a post build event.

Ben