Dapper - Result Multi-Type

Description

ExecuteReader method is an extension method which can be called from any object of type IDbConnection. It can execute a query and map the result to a list of different types.

  1. string sql = "SELECT * FROM Invoice;";
  3. using (var connection = My.ConnectionFactory())
  4. {
  5.     connection.Open();
  7.     var invoices = new List<Invoice>();
  9.     using (var reader = connection.ExecuteReader(sql))
  10.     {
  11.         var storeInvoiceParser = reader.GetRowParser<StoreInvoice>();
  12.         var webInvoiceParser = reader.GetRowParser<WebInvoice>();
  14.         while (reader.Read())
  15.         {
  16.             Invoice invoice;
  18.             switch ((InvoiceKind) reader.GetInt32(reader.GetOrdinal("Kind")))
  19.             {
  20.                 case InvoiceKind.StoreInvoice:
  21.                     invoice = storeInvoiceParser(reader);
  22.                     break;
  23.                 case InvoiceKind.WebInvoice:
  24.                     invoice = webInvoiceParser(reader);
  25.                     break;
  26.                 default:
  27.                     throw new Exception(ExceptionMessage.GeneralException);
  28.             }
  30.             invoices.Add(invoice);
  31.         }
  32.     }
  33. }