标签: objectstatemanager

当我迭代通过ObjectStateEntries我期望[t]变量名称将是MY_ENTITY

foreach (ObjectStateEntry entry in context.ObjectStateManager.GetObjectStateEntries(EntityState.Deleted))
{
    Type t = entry.Entity.GetType();
    ...
}

但我是真实的

System.Data.Entity.DynamicProxies.MY_ENTITY_vgfg7s7wyd7c7vgvgv.....

如何确定可以将当前条目转换为MY_ENTITY类型？

我试图将一个实体附加到ObjectContext.当我这样做时,抛出以下InvalidOperationException:

An object with the same key already exists in the ObjectStateManager.
The ObjectStateManager cannot track multiple objects with the same key.

我检查了对象状态管理器,该项目不存在:

//Data context is actually the object context.
ObjectStateEntry contact;
while ( //Should only work once since it should be true if the item was attached
          !DataContext.ObjectStateManager.
          TryGetObjectStateEntry(Contact, out contact)
      )
      DataContext.Attach(Contact); //Here is the exception thrown.

或者看看这个抽象的例子并告诉我它是否有意义:

EntityState state = Contact.EntityState; //Detached

DataContext.Attach(Contact); //Throws the exception.
DataContext.AttachTo("Entities.Contacts", Contact); //Throws the Exception

var detached = DataContext.ObjectStateManager.
                   GetObjectStateEntries(EntityState.Detached);
//InvalidArgumentException …

如何更新数据存储中的所有脏实体,并将更改后的值重置为原始存储值？

ObjectContext.Refresh方法需要刷新实体作为参数.

如果我修改POCO实体的属性,但重置它,EntityFramework仍然表示存在更改.

Property "Name": Value "Test" (original value) 
              -> Value "Test123" (value changed by UI) 
              -> Value "Test" (value changed by UI to original value)

已修改的条目:

var objectStateEntries = 
    _db.ObjectStateManager.GetObjectStateEntries(
        EntityState.Added | 
        EntityState.Deleted | 
        EntityState.Modified);

你怎么处理这个案子？

我有以下HttpPostDelete() 方法，它在我的 MVC5 应用程序中工作。据我所知，与此控制器、视图甚至模型相关的任何内容都没有发生变化。

    // POST: Admin/UserManagement/Delete/5
    [HttpPost, ActionName("DeleteConfirmed")]
    [ValidateAntiForgeryToken]
    public async Task<ActionResult> DeleteConfirmed(string id)
    {
        ApplicationUser applicationUser = db.Users.Find(id);
        if (applicationUser == null)
        {
            ModelState.AddModelError("", "Failed to find User ID for deletion.");
        }
        else
        {
            IdentityResult result = await UserManager.DeleteAsync(applicationUser);
            if (result.Succeeded)
            {
                await db.SaveChangesAsync();
                return RedirectToAction("Index", "UserManagement");
            }
            else
            {
                ModelState.AddModelError("", "Failed to Delete User.");
                var errors = string.Join(",", result.Errors);
                ModelState.AddModelError("", errors);
            }
        }

        return View(applicationUser);
    }

用户管理器部分：

[CustomAuthorization(myRoles = "Admin")]
public class UserManagementController : Controller …