Creating a constant Dictionary in C#

Question

What is the most efficient way to create a constant (never changes at runtime) mapping of strings to ints?

I\'ve tried us

Answer 1

If using 4.5+ Framework I would use ReadOnlyDictionary (also ReadOnly Collection for lists) to do readonly mappings/constants. It's implemented in the following way.

static class SomeClass
{
    static readonly ReadOnlyDictionary SOME_MAPPING 
        = new ReadOnlyDictionary(
            new Dictionary()
            {
                { "One", 1 },
                { "Two", 2 }
            }
        )
}