Unmodifiable lists in C#

Question

In Java, one can use the Collections#unmodifiableList() method to create an unmodifiable list from an existing List object. Is there any counterpart in C# ? I'm new to the language and haven't been able to find anything like this in the MSDN docs.

There are quite a few questions covering this, including: http://stackoverflow.com/questions/1326574/properly-exposing-a-listt — Ruben Bartelink, Nov 10 '09 at 20:29
Net framework offers that http://stackoverflow.com/questions/984042/unmodifiablelist-in-net-4-0 — Captain Comic, Nov 10 '09 at 20:21

score 21 · Accepted Answer · answered Nov 10 '09 at 20:19

21

ReadOnlyCollection

var dinosaurs = new List<string>();

dinosaurs.Add("Tyrannosaurus");
dinosaurs.Add("Amargasaurus");
dinosaurs.Add("Deinonychus");
dinosaurs.Add("Compsognathus");

var readOnlyDinosaurs = new ReadOnlyCollection<string>(dinosaurs);

answered Nov 10 '09 at 20:19

Bob

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Exactly what I'm looking for, thank you. I guess I haven't gotten used to how to search the MSDN site yet. – Alex Marshall Nov 10 '09 at 20:22
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The best search for MSDN is google :) But I knew it was called ReadOnlyCollection, If you are searching for Unmodifiable list you might have less results. – Bob Nov 10 '09 at 20:23
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The last line can be `var readonlyDinosaurs = dinosaurs.AsReadOnly()` – Ruben Bartelink Nov 10 '09 at 20:30
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Note that this does not actually make the collection itself read-only. Rather, it gives you a read-only wrapper around the mutable collection; attempts to mutate the wrapper will throw exceptions, but anyone who can get a reference to the original collection can still mutate it. – Eric Lippert Nov 10 '09 at 21:25

Unmodifiable lists in C#

1 Answers1