c# - Collection as key in Dictionary -


i have dictionary this:

var dic = dictionary<collection<myobject>, string>

then add entry this:

dic.add(myobjcoll, "1");

where myobjcoll contains single entry

on second run try add entry dic myobjcoll has 2 entries (one of them same 1 in first run) , exception key exists.

what missing here? expect dictionary key collection , surely 2 collections different number of entries cannot identical.

edit: happened myobjcoll initialized outside foreach , during second iteration updated. thought new collection 2 entries old 1 entry collection additional entry added.

to elaborate bit on issue:

i have collection of product row objects. each product identification object consisting of collection of key value pairs:

collection<productkeyvaluepair> productidentification; myproductrow.productidentification = productidentification;

i have construct collection of productkeyvaluepairs defining "owner" of each product row object (one product row object can have multiple owners) , need add each owner correspoding procuct row object(s). traditional many many common key collection of keyvaluepairs.

hard explain it's down legacy data returned old systems running on mainframe , stored in hierarchical database of sort :-/

keys in dictionaries expected immutable while performing role key. if change value of gethashcode() or equals(object) undefined behavior.

(also if collection not implement gethashcode() , equals(object) use members contains comparison reference container object itself)


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