How to properly use IReadOnlyDictionary?

Question

From msdn:

Represents a generic read-only collection of key/value pairs.

However consider following:

class Test
{
           


        

Answer 1

.NET 4.5 introduced the ReadOnlyDictionary type that you could use. It has a constructor that accepts an existing dictionary.

When targeting lower framework versions, use the wrapper as explained in Is there a read-only generic dictionary available in .NET? and Does C# have a way of giving me an immutable Dictionary?.

Please note that when using the latter class, the collection initializer syntax won't work; that gets compiled to Add() calls.