PostgreSQL 連線，存取資料方式。使用 C# WinFrom

NuGet 安裝 Npgsql。 (圖1)

圖1

        NuGet 安裝 Npgsql。(圖2)

圖2

安裝成功後，「參考」會有 Npgsql。(圖3)

圖3

使用 ConfigurationManager 需加入 System.configuration 至「參考」 (圖4)

圖4

======= 程式範例 回傳 DataTable

======= 參考資料 https://www.npgsql.org/doc/index.html

       public static DataTable Npgsql_Data(String sql)

       {

           //參考資料

           //https://www.npgsql.org/doc/index.html

           String connstr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;

           DataTable dt = new DataTable();

           using (Npgsql.NpgsqlConnection conn = new Npgsql.NpgsqlConnection(connstr))

           {

               conn.Open();

               using (var cmd = new Npgsql.NpgsqlCommand())

               {

                   cmd.Connection = conn;

                   cmd.CommandText = sql;

                   //執行不Query的方式

                   //cmd.ExecuteNonQuery();

                   Npgsql.NpgsqlDataReader dr = cmd.ExecuteReader();

                   dt.Load(dr);

               }

           }

           return dt;

       }

======= 程式範例 回傳 bool

======= 參考資料 https://www.npgsql.org/doc/index.html

       public static bool Npgsql_Data(String sql,String id,String value,String point)

       {

           bool success = false;

           //https://www.npgsql.org/doc/index.html

           String connstr = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;

           DataTable dt = new DataTable();

           using (Npgsql.NpgsqlConnection conn = new Npgsql.NpgsqlConnection(connstr))

           {

               conn.Open();

               using (var cmd = new Npgsql.NpgsqlCommand())

               {

                   cmd.Connection = conn;

                   cmd.CommandText = sql;

                   cmd.Parameters.AddWithValue("id", id);

                   cmd.Parameters.AddWithValue("value", value);

                   cmd.Parameters.AddWithValue("point", point);

                   if(cmd.ExecuteNonQuery() > 0)

                   {

                       success = true;

                   }else

                   {

                       success = false;

                   }

                   

               }

               

           }

           return success;

       }