c# posgre 接続 createdb

Program.cs

using System;
using Npgsql;

namespace db02
{
    class Program
    {
        static void Main(string[] args){

        //接続文字列
        NpgsqlConnection conn = new NpgsqlConnection("Server=localhost;Port=5432;User ID=postgres;Database=postgres;Password=Chatdb01;Enlist=true");

            conn.Open();
            try {
                NpgsqlCommand command = new NpgsqlCommand("DROP DATABASE IF EXISTS test01", conn);
                command.ExecuteNonQuery();
                command = new NpgsqlCommand("CREATE DATABASE test01", conn);
                command.ExecuteNonQuery();
                string comment = "'Test Database " + DateTime.Now.ToString("yyyy.MM.dd HH:mm:ss") + "'";
                command = new NpgsqlCommand("COMMENT ON DATABASE test01 IS " + comment, conn);
                command.ExecuteNonQuery();
            } finally {
                conn.Close();
            }

            conn = new NpgsqlConnection("Server=localhost;Port=5432;User ID=postgres;Database=test01;Password=Chatdb01;Enlist=true");
            conn.Open();
            try {
                NpgsqlCommand command = new NpgsqlCommand("select version()", conn);
                command.ExecuteNonQuery();
                var serverversion = (String)command.ExecuteScalar();
                Console.WriteLine("PostgreSQL server version: {0}", serverversion);
            } finally {
            conn.Close();
            }
        }
    }
}