c# - Why does Hashtable implement both ICollection and IEnumerable? -

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• why arraylist implement ilist, icollection, ienumerable? 4 answers

in .net framework 3.5 (c# 3.0) why system.hashtable implement both icollection , ienumerable when implements idictionary inherits these 2 interfaces?

having these intefaces:

interface ifoo1 {...}  interface ifoo2: ifoo1{...} 

there no difference in terms of compilation between followings:

class myclass: ifoo2{...}  class myclass: ifoo2, ifoo1{...} 

the second declaration makes clearer developers interfaces myclass class implements. easier have @ documentation , see myclass implements ifoo1 interface, without digging ifoo2 interface.