Defining the one to many relationship in OnModelCreating using Entity Framework Core 3.1 - entity-framework

Question

I am new to Entity Framework Core 3.1 and trying to define the one-to-many relationship between two tables. I am currently struggling and getting compilation errors. Could somebody tell me what the problem could be.
The error is:
PersonNote does not contain the definition for PersonNote
I am currently getting is at line
entity.HasOne(d => d.PersonNote)
How else could I define one-to-many relationship?
The two tables are Person and PersonNote. One Person can have many PersonNotes. I have defined the models for them
public class Person
{
public int Id { get; set; }
public int? TitleId { get; set; }
public string FirstName { get; set; }
public string FirstNamePref { get; set; }
public string MiddleName { get; set; }
public string LastName { get; set; }
public DateTime? DateOfBirth { get; set; }
public string Gender { get; set; }
public int AddressId { get; set; }
public string TelephoneNumber { get; set; }
public string MobileNumber { get; set; }
public string Email { get; set; }
public int? PartnerId { get; set; }
public bool Enabled { get; set; }
public string CreatedBy { get; set; }
public DateTime Created { get; set; }
public string ModifiedBy { get; set; }
public DateTime Modified { get; set; }
[DatabaseGenerated(DatabaseGeneratedOption.Computed)]
public DateTime RecordStartDateTime { get; set; }
[DatabaseGenerated(DatabaseGeneratedOption.Computed)]
public DateTime RecordEndDateTime { get; set; }
public Address Address { get; set; }
public Title Title { get; set; }
public Client Client { get; set; }
internal static IEnumerable<object> Include(Func<object, object> p)
{
throw new NotImplementedException();
}
public PersonNote PersonNote { get; set; }
}
public class PersonNote
{
public int Id { get; set; }
public int PersonId { get; set; }
public string Note { get; set; }
public int AuthorId { get; set; }
public string CreatedBy { get; set; }
public DateTime Created { get; set; }
[DatabaseGenerated(DatabaseGeneratedOption.Computed)]
public DateTime RecordStartDateTime { get; set; }
[DatabaseGenerated(DatabaseGeneratedOption.Computed)]
public DateTime RecordEndDateTime { get; set; }
}
public IEnumerable<PersonNote> GetPersonNotes(int personId)
{
var PersonNotes = PersonNote
.Include(x => x.)
.Where(x => x.Id == personId)
.ToList();
return PersonNotes;
}
I have tried the following in OnModelCreating:
modelBuilder.Entity<PersonNote>(entity =>
{
entity.ToTable("PersonNote", "common");
entity.HasOne(d => d.PersonNote)
.WithMany(p => p.Person)
.HasForeignKey(d => d.PersonId)
.OnDelete(DeleteBehavior.ClientSetNull)
.HasConstraintName("FK_commonPersonNote_commonPerson");
});

Answer 1

You should have have something like this (other properties are omitted):
class Person
{
[Key]
public int Id { get; set; }
public List<PersonNote> PersonNotes { get; set; }
}
class PersonNote
{
[Key]
public int Id { get; set; }
public int PersonId { get; set; }
}
class StackOverflow : DbContext
{
public DbSet<Person> Persons { get; set; }
public DbSet<PersonNote> PersonNotes { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Person>()
.HasMany(p => p.PersonNotes)
.WithOne()
.HasForeignKey(p => p.PersonId);
}
}