.net - Is there a generic collection with a key/value pair where key can occur more than once? -

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i want use generic collection dictionary, dictionary requires every key unique. have multiple values same "key", need generic collection allow that.

i realize makes key no longer key, don't know else call it.

several options consider:

  • use dictionary<tkey, list<tvalue>> — keep list of values each key, not preventing duplicate values same key (i.e. duplicate pairs);
  • use dictionary<tkey, hashset<tvalue>> — keep set of value each key, preventing duplicate values same key;
  • use list<keyvaluepair<tkey, tvalue>> — keep list of pair, not preventing duplicate values same key.

note in latter case keyvaluepair struct, not class, hence implies bit different handling.

the right option depends on actual use case.


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