How to Pass two connection string in Nhibernate in

I faced problem in my application: I have two databases and I want to access both with NHibernate, but in the configration file I have only one connection string for one database. So how can I pass more than one connection string to NHibernate?

回答1:

I usually define connection strings in my app.config:

  <connectionStrings>
    <add name="connection1" connectionString="Data Source=;User ID=;Password=;" />
    <add name="connection2" connectionString="Data Source=;User ID=;Password=;" />
  </connectionStrings>

then I create 2 separate (nhibernate) config files with nhibernate configurations (in case you have 2 different databases).

I use one class which allows me to create a session factory:

    public class NHibernateSessionFactory
    {
        private ISessionFactory sessionFactory;

        private readonly string ConnectionString = "";
        private readonly string nHibernateConfigFile = "";

        public NHibernateSessionFactory(String connectionString, string nHConfigFile)
        {
            this.ConnectionString = connectionString;
            this.nHibernateConfigFile = nHConfigFile;
        }

        public ISessionFactory SessionFactory
        {
            get { return sessionFactory ?? (sessionFactory = CreateSessionFactory()); }
        }

        private ISessionFactory CreateSessionFactory()
        {
            Configuration cfg;
            cfg = new Configuration().Configure(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, this.nHibernateConfigFile));

            // With this row below Nhibernate searches for the connection string inside the App.Config.
            // cfg.SetProperty(NHibernate.Cfg.Environment.ConnectionStringName, System.Environment.MachineName);
            cfg.SetProperty(NHibernate.Cfg.Environment.ConnectionString, this.ConnectionString);

#if DEBUG
            cfg.SetProperty(NHibernate.Cfg.Environment.GenerateStatistics, "true");
            cfg.SetProperty(NHibernate.Cfg.Environment.ShowSql, "true");
#endif

            return (cfg.BuildSessionFactory());
        }
    }

Now I can create many different session factories with their own specific configuration:

var sessionFactory1 = new NHibernateSessionFactory("connection string 1", "sql.nhibernate").SessionFactory;

var sessionFactory2 = new NHibernateSessionFactory("connection string 2", "ora.nhibernate").SessionFactory;

You can find more info here.

回答2:

For each Database, you need a own SessionFactory. If you omit the ConnectionString in your NH config, you can specify it in Code while building your Sessionfactory:

var sessionFactory1 = new Configuration()
                    .Configure()
                    .SetProperty("connection.connection_string", "First Connection String").BuildSessionFactory();

var sessionFactory2 = new Configuration()
                    .Configure()
                    .SetProperty("connection.connection_string", "Second Connection String").BuildSessionFactory();