Dynamically insert the database name in the connection string

Hi,

I want to enable the usr to insert the name of the database. Than this name I want to use in the connection string in this format

 string connString = @"
      server = server1;
      integrated security = false;
      database = the inserted databaseName by the user //??
      user id  = user;
      password = password;

Can anybody help me please?

Thanks