ASP.NET Core Entity Framework SQL Query SELECT - entity-framework

Question

I am one of the many struggling to "upgrade" from ASP.NET to ASP.NET Core.
In the ASP.NET project, I made database calls from my DAL like so:
var result = context.Database.SqlQuery<Object_VM>("EXEC [sp_Object_GetByKey] #Key",
new SqlParameter("#Key", Key))
.FirstOrDefault();
return result;
My viewmodel has additional fields that my object does not, such as aggregates of related tables. It seems unnecessary and counter intuitive to include such fields in a database / table structure. My stored procedure calculates all those things and returns the fields as should be displayed, but not stored.
I see that ASP.NET Core has removed this functionality. I am trying to continue to use stored procedures and load view models (and thus not have the entity in the database). I see options like the following, but as a result I get "2", the number of rows being returned (or another mysterious result?).
using(context)
{
string cmd = "EXEC [sp_Object_getAll]";
var result = context.Database.ExecuteSQLCommand(cmd);
}
But that won't work because context.Database.ExecuteSQLCommand is only for altering the database, not "selecting".
I've also seen the following as a solution, but the code will not compile for me, as "set" is really set<TEntity>, and there isn't a database entity for this viewmodel.
var result = context.Set().FromSql("EXEC [sp_Object_getAll]");
Any assistance much appreciated.

Answer 1

Solution:
(per Tseng's advice)
On the GitHub Entity Framework Issues page, there is a discussion about this problem. One user recommends creating your own class to handle this sort of requests, and another adds an additional method that makes it run smoother. I changed the methods slights to accept slightly different params.
Here is my adaptation (very little difference), for others that are also looking for a solution:
Method in DAL
public JsonResult GetObjectByID(int ID)
{
SqlParameter[] parms = new SqlParameter[] { new SqlParameter("#ID", ID) };
var result = RDFacadeExtensions.GetModelFromQuery<Object_List_VM>(context, "EXEC [sp_Object_GetList] #ID", parms);
return new JsonResult(result.ToList(), setting);
}
Additional Class
public static class RDFacadeExtensions
{
public static RelationalDataReader ExecuteSqlQuery(
this DatabaseFacade databaseFacade,
string sql,
SqlParameter[] parameters)
{
var concurrencyDetector = databaseFacade.GetService<IConcurrencyDetector>();
using (concurrencyDetector.EnterCriticalSection())
{
var rawSqlCommand = databaseFacade
.GetService<IRawSqlCommandBuilder>()
.Build(sql, parameters);
return rawSqlCommand
.RelationalCommand
.ExecuteReader(
databaseFacade.GetService<IRelationalConnection>(),
parameterValues: rawSqlCommand.ParameterValues);
}
}
public static IEnumerable<T> GetModelFromQuery<T>(
DbContext context,
string sql,
SqlParameter[] parameters)
where T : new()
{
DatabaseFacade databaseFacade = new DatabaseFacade(context);
using (DbDataReader dr = databaseFacade.ExecuteSqlQuery(sql, parameters).DbDataReader)
{
List<T> lst = new List<T>();
PropertyInfo[] props = typeof(T).GetProperties();
while (dr.Read())
{
T t = new T();
IEnumerable<string> actualNames = dr.GetColumnSchema().Select(o => o.ColumnName);
for (int i = 0; i < props.Length; ++i)
{
PropertyInfo pi = props[i];
if (!pi.CanWrite) continue;
System.ComponentModel.DataAnnotations.Schema.ColumnAttribute ca = pi.GetCustomAttribute(typeof(System.ComponentModel.DataAnnotations.Schema.ColumnAttribute)) as System.ComponentModel.DataAnnotations.Schema.ColumnAttribute;
string name = ca?.Name ?? pi.Name;
if (pi == null) continue;
if (!actualNames.Contains(name)) { continue; }
object value = dr[name];
Type pt = pi.DeclaringType;
bool nullable = pt.GetTypeInfo().IsGenericType && pt.GetGenericTypeDefinition() == typeof(Nullable<>);
if (value == DBNull.Value) { value = null; }
if (value == null && pt.GetTypeInfo().IsValueType && !nullable)
{ value = Activator.CreateInstance(pt); }
pi.SetValue(t, value);
}//for i
lst.Add(t);
}//while
return lst;
}//using dr
}