ArrayList
declares that it implements the IList
, ICollection
, and IEnumeralbe
interfaces.
Why not only implement IList
, because IList
is also derived from ICollection
, and ICollection
is derived from IEnumerable
.
What's the purpose of this kind of declaration? There are many cases like this in .NET BCL.
See Question&Answers more detail:
os 与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…