Npgsql.NpgsqlConnection.ChangeDatabase C# (CSharp) Method

        public override void ChangeDatabase(String dbName)
        {
            CheckNotDisposed();

            NpgsqlEventLog.LogMethodEnter(LogLevel.Debug, CLASSNAME, "ChangeDatabase", dbName);

            if (dbName == null)
            {
                throw new ArgumentNullException("dbName");
            }

            if (string.IsNullOrEmpty(dbName))
            {
                throw new ArgumentOutOfRangeException("dbName", dbName, String.Format(resman.GetString("Exception_InvalidDbName")));
            }

            String oldDatabaseName = Database;

            Close();

            // Mutating the current `settings` object would invalidate the cached instance, so work on a copy instead.
            settings = settings.Clone();
            settings[Keywords.Database] = dbName;
            _connectionString = null;

            Open();
        }

		/// <summary>
		/// Default constructor.
		/// </summary>
		/// <param name="intitString"></param>
		public pgsql_API(string intitString)
		{
			// connectionstring=
			string[] parameters = intitString.Replace("\r\n","\n").Split('\n');
			foreach(string param in parameters){
				if(param.ToLower().IndexOf("connectionstring=") > -1){
					m_ConStr = param.Substring(17);
				}
			}
         
            SqlConnectionStringBuilder b = new SqlConnectionStringBuilder(m_ConStr);
            string database = b.InitialCatalog;
            b.InitialCatalog = "";              
            using(NpgsqlConnection con = new NpgsqlConnection(b.ToString().ToLower().Replace("data source","server"))){                    
                con.Open();

                // See if database exists
                try{
                    con.ChangeDatabase(database);
                }
                catch{
                    // Database don't exist, try to create it

                    try{
                        con.Close();
                        con.ConnectionString = b.ToString().ToLower().Replace("data source","server");
                        con.Open();


                        NpgsqlCommand cmd = new NpgsqlCommand();
                        cmd.Connection = con;
                        cmd.CommandType = CommandType.Text;
                        cmd.CommandText = "create database \"" + database + "\"";
                        cmd.ExecuteNonQuery();
                        con.ChangeDatabase(database);

                        // Create tables
                        cmd.CommandText = ResManager.GetText("tables.sql",System.Text.Encoding.Default);
                        cmd.ExecuteNonQuery();

                        // Create procedures
                        cmd.CommandText = ResManager.GetText("procedures.sql",System.Text.Encoding.Default);
                        cmd.ExecuteNonQuery();
                    }
                    catch{
                        throw new Exception("Database '" + database + "' doesn''t exist ! Create failed, specified user doesn't have enough permisssions to create database ! Create database manually.");
                    }                    
                }
            }
		}