c# - ObjectStateManager 没有定义问题

Question

我遇到了 ObjectStateManager 的问题。

我正在使用 System.Data.Entity 和 System.Data.Objects 但是它没有显示 ObjectStateManager< 的定义.

SampleContext db = new SampleContext();
Employees employeeFromDB = db.Employees.Single(x => x.Id == employee.Id);

employeeFromDB.FullName = employee.FullName;
employeeFromDB.Gender = employee.Gender;
employeeFromDB.Age = employee.Age;
employeeFromDB.HireDate = employee.HireDate;
employeeFromDB.Salary = employee.Salary;
employeeFromDB.PersonalWebSite = employee.PersonalWebSite;

db.ObjectStateManager.ChangeObjectState(employeeFromDB, System.Data.EntityState.Modified);
db.SaveChanges();
return RedirectToAction("Details", new {Id = employee.Id});

Answer 1

发件人:Why does the ObjectStateManager property not exist in my db context?

var manager = ((IObjectContextAdapter)db).ObjectContext.ObjectStateManager;