[This is preliminary documentation and is subject to change.]
Adds an object to the collection, but only if the object is not
already contained in it.
Declaration Syntax| C# |
public bool AddIfAbsent( T obj )
Parameters- obj (T)
- The object to add to the collection.
Return ValueTrue if the object was added to the collection, false if it was
already contained in the collection.
RemarksIf it is added, and the collection is ordered, then the Order property in the object will be set to
the position in the list at which it is added.
Exceptions| Exception | Condition |
|---|---|
| InvalidOperationException | Thrown if you add an object
which is invalid (Persistent.IsInvalid returns
true). |