// Entity Framework Classic

// Doc: https://entityframework-classic.net/query-result-filter

​

// @nuget: Z.EntityFramework.Classic

​

using System;

using System.Linq;

using System.Data.Entity;

​

public class Program

{

    public static void Main()

    {

        using (var context = new EntityContext())

        {

            // Gets the `QueryFilter` EntityType.

            var filter = context.Configuration.QueryResultFilter.Filter<ISoftDelete>(customer => !customer.IsDeleted || context.DisplaySoftDelete());

            Console.WriteLine("2 - Gets the `QueryFilter` EntityType : " +  filter.EntityType.Name);

        }

    }

​

    public class EntityContext : DbContext

    {

        public EntityContext() : base(FiddleHelper.GetConnectionStringSqlServer())

        {       

        }

        public bool DisplaySoftDelete()

        {

            // Check for example if current user has admin right

            return false;

        }

        public DbSet<Customer> Customers { get; set; }

    }

    public interface ISoftDelete

    {

        bool IsDeleted { get; set; }

    }

    public class Customer : ISoftDelete

    {

        public int CustomerID { get; set; }

        public string Name { get; set; }

        public string Description { get; set; }

        public bool IsDeleted { get; set; }

    }

}