generic class supports duplicated key [duplicate]

This question already has answers here: 开发者_开发百科 Closed 12 years ago.

Possible Duplicate:

Duplicate keys in .NET dictionaries?

I want to use a kind of dictionary which can support duplicated keys. Is there any builtin support in .Net framework?

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Yes, using the Lookup class.

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No but you can use List it doesnt have key values instead of you can store like List.add( key,value)