Article: http://www.zzzprojects.com/entity-framework-extensions/docs/how/soft-delete

entity-framework-extensions-docs-how-soft-delete-example-1.cs

using (var ctx = new CurrentContext())
{
    var lastLogin = DateTime.Now.AddYears(-2);
    var list = ctx.Customers.Where(x => x.LastLogin < lastLogin).ToList();
    ctx.Customers.RemoveRange(list);
    
    // HOW to automatically handle soft delete?
    ctx.BulkSaveChanges();
}

entity-framework-extensions-docs-how-soft-delete-example-2.cs

EntityFrameworkManager.PreBulkSaveChanges = context =>
{
    foreach (var entry in context.ChangeTracker.Entries())
    {
        if (entry.State == EntityState.Deleted && entry.Entity is Customer)
        {
            entry.State = EntityState.Modified;
            ((Customer) entry.Entity).IsDeleted = true;
        }
    }
};

using (var ctx = new CurrentContext())
{
    var lastLogin = DateTime.Now.AddYears(-2);
    var list = ctx.Customers.Where(x => x.LastLogin < lastLogin).ToList();
    ctx.Customers.RemoveRange(list);
    ctx.BulkSaveChanges();
}

entity-framework-extensions-docs-how-soft-delete-example-3.cs

using (var ctx = new CurrentContext())
{
    var lastLogin = DateTime.Now.AddYears(-2);
    var list = ctx.Customers.Where(x => x.LastLogin < lastLogin).ToList();
    
    // HOW to automatically handle soft delete?
    ctx.BulkDelete(list);
}

entity-framework-extensions-docs-how-soft-delete-example-4.cs

public static class Extensions
{
    public static void BulkHardOrSoftDelete<T>(this DbContext ctx, IEnumerable<T> items) where T : class
    {
        var hardDelete = new List<T>();
        var softDelete = new List<T>();

        foreach (var item in items)
        {
            var customer = item as Customer;
            if (customer != null)
            {
                customer.IsDeleted = true;
                softDelete.Add(item);
            }
            else
            {
                hardDelete.Add(item);
            }
        }

        if (hardDelete.Count > 0)
        {
            ctx.BulkDelete(hardDelete);
        }
        if (softDelete.Count > 0)
        {
            ctx.BulkUpdate(softDelete);
        }
    }
}

using (var ctx = new CurrentContext())
{
	var lastLogin = DateTime.Now.AddYears(-2);
	var list = ctx.Customers.Where(x => x.LastLogin < lastLogin).ToList();

	ctx.BulkHardOrSoftDelete(list);
}