How to update one field of specific records using Entity Framework?

Question

I want update family of a person who his name is pejman. This is my object Class:

public class Person
{
    public int Id { get; set; }
    public string FirstNa         


        

Answer 1

For resolving this error i got values by ID from database stored in Var Temprc. Then updated the field Password which i wont to update. Then attached temprc to my Userregistrations model. Then Marked PasswordConfirm isModified. then Savechanges();

using (var db = new Entities())
                {                       
                    var temprc = _reg.GetUserByID(Convert.ToInt32(Session["LogedUserID"]));
                    temprc.PasswordConfirm = U.NewPassword;
                    db.Userregistrations.Attach(temprc);
                    db.Entry(temprc).Property(x => x.PasswordConfirm).IsModified = true;
                    db.SaveChanges();    
                }