C# Indexer versus List of Classes

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Hey guys, Ive come accross a new concept in C# that I am having a hard time finding a use for - Indexers. I know that an indexer is a way to index classes like arrays, but what is the advantage of an indexer over a generic (or not) list of classes?

Could someone elaborate on some uses/applications of an indexer?

Posted 17-May-11 15:52pm

Isaiah83

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Sergey Alexandrovich Kryukov · Accepted Answer · 2011-05-17T15:56:00

Solution 1

One word: indexer is more abstract. There are many cases when there is no any container behind — the property is calculated on the fly. I widely use this feature; you can consider it as a neat syntax candy, compared to something like "FindElementByName" or "GetElementByIndex".

[EDIT]
You can find interesting application in my code sample in one of my answers here:
Location of a refernced object in an array?[^].

—SA

Posted 17-May-11 15:56pm

Sergey Alexandrovich Kryukov

Updated 17-May-11 16:27pm

v3

Comments

Isaiah83 17-May-11 22:03pm

Clarify what you mean by container, please. Do you mean there isn't a specific collection like List/ArrayList/Array to define the collection?

Sergey Alexandrovich Kryukov 17-May-11 22:29pm

Yes, but anything that can be indexed with "[]". With indexers, the index type can be anything.
Please see my code sample; I just added a reference for you. Ask another question is it's not clear.
--SA

Isaiah83 17-May-11 23:00pm

Now I can see the power of indexers. It seems that being able to index with anything (datatype, user defined etc..) is really desireable. I need more time to decipher your example, but thank you for sharing as it did give me some insight. 5/5. Cheers

Sergey Alexandrovich Kryukov 17-May-11 23:05pm

Great! You're welcome.
Thanks for accepting this answer. Your follow-up questions are welcome.

Good luck, call again.
--SA