Entity Framework execute stored procedure with params - entity-framework

Question

Ok, hope to not get too many flags, but it's to annoying.
I have a method in my controller which calls a method from another class:
offerForCreate.Rating = CalculateRating.CreateRating(addOffer);
and entire called class :
public class CalculateRating
{
private readonly DataContext mainContext;
public CalculateRating(DataContext mainContext)
{
this.mainContext = mainContext;
}
// calcul rating oferte noi
public decimal CreateRating(OfferForCreate offer)
{
decimal rating = mainContext.Database.FromSql<decimal>("RatingCalculator", offer.locationId, offer.typeId);
return rating;
}
}
I get an error when try to execute this procedure:
Error CS1061: 'DatabaseFacade' does not contain a definition for 'FromSql' and no extension method 'FromSql' accepting a first argument of type 'DatabaseFacade' could be found
and another if I don't create an instance of CalculateRating class in my controller :
Controllers\AnnouncesController.cs(127,37): error CS0120: An object reference is required for the non-static field, method, or property 'CalculateRating.CreateRating(OfferForCreate)
Everywhere I see must specify the entity, but what entity I can specify if my stored procedure use multiple tables?
Asp.Net Core Web API

Answer 1

You can execute stored proc like this:
using (var command = mainContext.Database.GetDbConnection().CreateCommand())
{
command.CommandType = System.Data.CommandType.StoredProcedure;
command.CommandText = "dbo.RatingCalculator";
var locationIdParam = new System.Data.SqlClient.SqlParameter("#locationId", System.Data.SqlDbType.Int);
locationIdParam .Value = offer.locationId;
//DO same for typeId parameter
//Params to Parameters collection
command.Parameters.Add(locationIdParam);
command.Connection.Open();
return (double)command.ExecuteScalar();
}
Controllers\AnnouncesController.cs(127,37): error CS0120: An object reference is required for the non-static field, method, or property 'CalculateRating.CreateRating(OfferForCreate)
This error is occuring because if you declare CalculateRating as static you can not reference in non-static field mainContext.
You should create an instance of your CalculateRating class using Dependency Injection. Here are steps:
Create an interface ICalculateRating
public interface ICalculateRating {
decimal CreateRating(OfferForCreate offer);
}
Update CalculateRating class to implement ICalculateRating
Register the DBContext and ICalculateRating mappings in ConfigureServices method of Startup.cs file like this:
services.AddDbContext<DbContext>(opts=> { opts.UseSqlServer("sqlserver conntection string") }, ServiceLifetime.Scoped);
services.AddTransient<ICalculateRating, CalculateRating>();
In your controller constructor, input an argument of type ICalculateRating which will be injected by Microsoft Dependency Injection framework at runtime:
private readonly ICalculateRating _calculateRating;
public MyController(ICalculateRating calculateRating) {
_calculateRating = calculateRating;
}
You can then call the method like this:
offerForCreate.Rating = _calculateRating.CreateRating(addOffer);