// Entity Framework Classic

// Doc: https://entityframework-classic.net/bulk-delete

​

// @nuget: Z.EntityFramework.Classic

​

using System;

using System.Collections.Generic;

using System.Linq;

using System.Data.Entity;

using System.Threading.Tasks;

using System.Threading;

​

public class Program

{   

    public static void Main()

    {

        MainAsync().Wait();

    }

    public static async Task MainAsync()

    {

        using (var context = new EntityContext())

        {   

            var customers = GenerateCustomers(5);

            FiddleHelper.WriteTable("1 - Before", context.Customers.ToList());  

            CancellationTokenSource tcs = new CancellationTokenSource();

            CancellationToken token = new CancellationToken();

            // Easy to use

            await context.BulkDeleteAsync(customers, token);

            Thread.Sleep(1000);

            tcs.Cancel();

            FiddleHelper.WriteTable("2 - After", context.Customers.ToList());   

        }

        using(var context = new EntityContext())

        {

            var customers = GenerateCustomers(5);

            FiddleHelper.WriteTable("3 - Before", context.Customers.ToList());  

            // Easy to use

            context.BulkDelete(customers, options => options.ColumnPrimaryKeyExpression = customer => customer.Code);

            FiddleHelper.WriteTable("4 - After", context.Customers.ToList());   

        }

    }

    public static List<Customer> GenerateCustomers(int count)

    {

        var list = new List<Customer>();

        for(int i = 0; i < count; i++)

        {

            list.Add(new Customer() { Code = "Code_" + i, FirstName = "FirstName_" + i, LastName = "LastName_" + i });

        }

        using (var context = new EntityContext())

        {

            context.BulkInsert(list);

        }

        return list;

    }

​

    public class EntityContext : DbContext

    {

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

        {

        }

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

    }

​

    public class Customer

    {

        public int CustomerID { get; set; }

        public string Code { get; set; }

        public string FirstName { get; set; }

        public string LastName { get; set; }

    }

}