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

A version from @user166390 answer with an added IEqualityComparer parameter to allow for case insensitive key comparison.

    public static T MergeLeft(this T me, params Dictionary[] others)
        where T : Dictionary, new()
    {
        return me.MergeLeft(me.Comparer, others);
    }

    public static T MergeLeft(this T me, IEqualityComparer comparer, params Dictionary[] others)
        where T : Dictionary, new()
    {
        T newMap = Activator.CreateInstance(typeof(T), new object[] { comparer }) as T;

        foreach (Dictionary src in 
            (new List> { me }).Concat(others))
        {
            // ^-- echk. Not quite there type-system.
            foreach (KeyValuePair p in src)
            {
                newMap[p.Key] = p.Value;
            }
        }
        return newMap;
    }