An XMS object
can have attributes and properties, which are characteristics of the object,
that are implemented in different ways.
- Attributes
- An object characteristic that is always present and occupies storage,
even if the attribute does not have a value. In this respect, an attribute
is similar to a field in a fixed length data structure. A distinguishing feature
of attributes is that each attribute has its own methods for setting and getting
its value.
- Properties
- A property of an object is present and occupies storage only after its
value is set. However, a property cannot be deleted (nor can the storage be
recovered) after its value has been set, although you can change its value. XMS provides a set
of generic methods for setting and getting property values.