How to automatically populate CreatedDate and ModifiedDate?

Question

I am learning ASP.NET Core MVC and my model is

namespace Joukyuu.Models
{
    public class Passage
    {
        public int PassageId { get; set; }
        publi         


        

Answer 1

For those who are using the asynchronous system (SaveChangesAsync) and .NET Core, it's better to override the DbContext's SaveChangesAsync method:

public override Task SaveChangesAsync(
    bool acceptAllChangesOnSuccess,
    CancellationToken cancellationToken = default(CancellationToken))
{
    var AddedEntities = ChangeTracker.Entries()
        .Where(E => E.State == EntityState.Added)
        .ToList();

    AddedEntities.ForEach(E =>
    {
        E.Property("CreationTime").CurrentValue = DateTime.Now;
    });

    var EditedEntities = ChangeTracker.Entries()
        .Where(E => E.State == EntityState.Modified)
        .ToList();

    EditedEntities.ForEach(E =>
    {
        E.Property("ModifiedDate").CurrentValue = DateTime.Now;
    });

    return base.SaveChangesAsync(acceptAllChangesOnSuccess, cancellationToken);
}

Also, you can define a base class or an interface for your models with these properties:

public class SaveConfig
{
    public DateTime CreationTime { get; set; }
    public DateTime? ModifiedDate { get; set; }
}