Question

//here is my data models:

public class People
{
    public int PeopleID { get; set; }

    [Required]
    public string Name { get; set; }
}

[Table("User")]
public class User : People
{
    [Required]
    public string LoginName { get; set; }

    [Required]
    public string PassWord { get; set; }

}

//and i stored an item into the People table

context.People.Add(new People { Name = “Jack” });

context.SaveChanges();

//and now “Jack” is promoted as an user of this system
//how can I update his data and let him has is LoginName and Password?

Answer 1

This is a common design mistake.

Objects can’t change their type; you shouldn’t be using inheritance in this case.

Instead, the User can have a reference to a Person (another hint: your entity names should be singular, regardless of what you name the table)