Handling varying number of result sets in Petapoco or Dapper?

Question

I have used QueryMultiple before for handling multiple result sets, but I knew the exact number of result sets being returned. In this case, when I call a stored proc with QueryMultiple, the number of result sets returned varies. Is it possible to handle this in PetaPoco or another orm such as Dapper?

Answer 1

Dapper's QueryMultiple method returns a GridReader; a GridReader has a .IsConsumed property that should change to true when you've read all the available result sets, so that might work:

using(var reader = conn.QueryMultiple(...)) {
    do {
        var data = reader.Read<...>().AsList();
        // ...
    } while(!reader.IsConsumed);
}

Alternatively, Dapper has an ExecuteReader method that just does the "pack the parameters and invoke step", and a GetTypeDeserializer method that exposes just the "materialize a row into an object" code, so you could manually combine those, i.e.:

using(var reader = conn.ExecuteReader(...)) {
    do {
        var parser = SqlMapper.GetTypeDeserializer(...);
        while(reader.Read()) {
            var obj = parser(reader);
            // ...
        }
    } while(reader.NextResult());
}

(I don't know much about petapoco, sorry)