Produces the union of the current collection and a passed collection (array). It adds to the current collection (array) missing elements from the specified collection (array).
A version for working with the collection that implements the ICollection<T> interface.
ICollection<T>* collection // collection
A version for working with an array.
T& array // array
[in] A collection with which the current set will be united.
[in] An array with which the current set will be united.
The result is written to the current collection (array).