Merging dictionaries in C#

Question

What\'s the best way to merge 2 or more dictionaries (Dictionary) in C#? (3.0 features like LINQ are fine).

I\'m thinking of a method signa

Answer 1

Here is a helper function I use:

using System.Collections.Generic;
namespace HelperMethods
{
    public static class MergeDictionaries
    {
        public static void Merge(this IDictionary first, IDictionary second)
        {
            if (second == null || first == null) return;
            foreach (var item in second) 
                if (!first.ContainsKey(item.Key)) 
                    first.Add(item.Key, item.Value);
        }
    }
}