why i can't update my entity witch contian navigation property? RRS feed

  • 问题

  • public void UpdateRC_User(RC_User currentRC_User)
            this.ObjectContext.AttachAsModified(currentMyEntity, this.ChangeSet.GetOriginal(currentMyEntity));

    Why my code here throw a exception:
    Value cannot be null.
    Parameter name: original

    I have one entity named RC_User, and RC_User contain a navigation property named RC_SecurityAdmin.
    when i update RC_User's property(not naviagtion) only, it'll  save entity rightly.
    when i update RC_User's property(not naviagtion) and inserting or deleting RC_SecurityAdmin, it'll save rightly too.
    when i inserting or deleting RC_SecurityAdmin only, it'll throw execption .....

    who can help me?

    2010年7月30日 9:10