how to check if object already exists in a list

Question

I have a list

  List myList

and I am adding items to a list and I want to check if that object is already in the list.

Answer 1

If you use EF core add

 .UseSerialColumn();

Example

modelBuilder.Entity(entity =>
        {
            entity.ToTable("jobs");

            entity.Property(e => e.Id)
                .HasColumnName("id")
                .UseSerialColumn();
});