public virtual extern void SetValue([In] ref _tagpropertykey key, [In] ref tag_inner_PROPVARIANT pValue);
 public virtual extern void GetAt([In] uint dwIndex, [In] ref tag_inner_PROPVARIANT pValue);
 public virtual extern void GetAt([In] uint index, [In, Out] ref _tagpropertykey pKey, [In, Out] ref tag_inner_PROPVARIANT pValue);