ASP.NET CORE using ADO.NET with AutoMapper - asp.net-core

Question

What is the proper way of using AutoMapper with ADO.NET in ASP.NET Core in generic way?
Also the SQL query has the same column names as in class of <T>
In specified example variable result is always empty list, so automapper could not map object properties to DbDataReader columns.
public class CustomDbContext : BaseRepository
{
readonly DbConnection dbConn;
public CustomDbContext(RepoDbContext context) : base(context)
{
dbConn = context.Database.GetDbConnection();
}
public async Task<List<T>> Get<T>(string sql) where T : class
{
var config = new AutoMapper.MapperConfiguration(cfg =>
{
cfg.CreateMap<DbDataReader, List<T>>();
});
var mapper = config.CreateMapper();
await dbConn.OpenAsync();
using (var command = dbConn.CreateCommand())
{
command.CommandText = sql;
var reader = await command.ExecuteReaderAsync();
var result = new List<T>();
if (reader.HasRows)
{
await reader.ReadAsync();
result = mapper.Map<DbDataReader, List<T>>(reader);
}
reader.Dispose();
return result;
}
}
}
Should I specify more detailed AutoMapper configuration or it can't be done this way?

Answer 1

Try using interfaces as IDataReader and IEnumerable instead of classes DbDataReader and List.
public async Task<List<T>> Get<T>(string sql) where T : class
{
var config = new AutoMapper.MapperConfiguration(cfg =>
{
cfg.CreateMap<IDataReader, IEnumerable<T>>();
});
var mapper = config.CreateMapper();
await dbConn.OpenAsync();
using (var command = dbConn.CreateCommand())
{
command.CommandText = sql;
var reader = await command.ExecuteReaderAsync();
var result = new List<T>();
if (reader.HasRows)
{
await reader.ReadAsync();
result = mapper.Map<IDataReader, IEnumerable<T>>(reader).ToList();
}
reader.Dispose();
return result;
}
}