// Entity Framework Extensions

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

​

// @nuget: Microsoft.EntityFrameworkCore.SqlServer

// @nuget: Z.EntityFramework.Extensions.EFCore

​

using System;

using Microsoft.EntityFrameworkCore;

using System.Collections.Generic;

using Microsoft.Data.SqlClient;

using System.Linq;

using System.Threading;

using System.Threading.Tasks;

public class Program

{   

    public static void Main()

    {

        MainAsync().Wait();

    }

    public static async Task MainAsync()

    {

        using (var context = new EntityContext())

        {

            context.Database.EnsureCreated();

        }

        var customers = SeedCustomer(5);

​

        using (var context = new EntityContext())

        {

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

            var toDelete = customers.Take(customers.Count() / 2);

            CancellationTokenSource tcs = new CancellationTokenSource();

            CancellationToken token = new CancellationToken();

            await context.BulkDeleteAsync(toDelete, options => options.BatchSize = 100, token);

            Thread.Sleep(1000);

            tcs.Cancel();

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

        }   

    }

​

    public static List<Customer> SeedCustomer(int count) 

    {

        List<Customer> list = new List<Customer>();

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

        {

            list.Add(new Customer() { Name = "Customer_" + i});

        }

        new EntityContext().BulkInsert(list);

        return list;

    }

​

    public class EntityContext : DbContext

    {

        public EntityContext() 

        {

        }

​

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)

        {

            optionsBuilder.UseSqlServer(new SqlConnection(FiddleHelper.GetConnectionStringSqlServer()));

​

            base.OnConfiguring(optionsBuilder);

        }

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

    }

    public class Customer

    {

        public int CustomerID { get; set; }

        public string Name { get; set; }

    }

}