// Entity Framework Classic

// Doc: https://entityframework-classic.net/audit

​

// @nuget: Z.EntityFramework.Classic

​

using System;

using System.Linq;

using System.Collections.Generic;

using System.Data.Entity;

using Z.EntityFramework.Classic;

​

public class Program

{

    public class EntityContext : DbContext

    {

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

        {

            // Add your configuration here

            // Excludes from the audit all properties unchanged which satisfy the predicate. Key properties are never excluded.

            this.Configuration.Audit.ExcludePropertyUnchanged(x => x.GetType() == typeof(Customer) && ((Customer)x).Description == "Description");

            this.Configuration.Audit.AutoSaveSet = this.XmlAuditEntries;

            this.Configuration.Audit.IsEnabled = true;

        }

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

        public DbSet<XmlAuditEntry> XmlAuditEntries { get; set; }

    }

    public static void Main()

    {

        using (var context = new EntityContext())

        {

            context.Configuration.Audit.IsEnabled = false;

            context.Customers.Add(new Customer() { Name = "Customer_A", Description = "Description" });

            // Save changes with Audit Enabled

            context.SaveChanges();

        }

        using (var context = new EntityContext())

        {

            context.Customers.ToList().ForEach(x => x.Description = "Update_1");

            // Save changes with Audit Enabled

            context.SaveChanges();

            // Display Audit Properties Trail

            var auditEntries = context.XmlAuditEntries.ToAuditEntries();

            FiddleHelper.WriteTable("1 - Entity Framework - All Unchanged Property Exclude (Key properties are never excluded);", auditEntries.SelectMany(x => x.Properties));

        }

        using (var context = new EntityContext())

        {           

            context.Customers.ToList().ForEach(x => x.Description = "Update_2");

            // Includes to the audit all properties unchanged which satisfy the predicate.

            context.Configuration.Audit.IncludePropertyUnchanged(x => x.GetType() == typeof(Customer) && ((Customer)x).Description == "Description");

            // Save changes with Audit Enabled

            context.SaveChanges();

            // Display Audit Properties Trail

            var auditEntries = context.XmlAuditEntries.ToAuditEntries();

            FiddleHelper.WriteTable("2 - Entity Framework - context.Configuration.Audit.IncludePropertyUnchanged(x => x.GetType() == typeof(Customer) && ((Customer)x).Description == \"Description\");", auditEntries.SelectMany(x => x.Properties));

        }

    }

    public class Customer

    {

        public int CustomerID { get; set; }

        public string Name { get; set; }

        public string Description { get; set; }

    }

}