How do I sum values from two dictionaries in C#?

Question

I have two dictionaries with the same structure:

Dictionary foo = new Dictionary() 
{
    {\"Table\", 5 },
    {\"Chair         


        

Answer 1

What about something like this?

var fooBar = foo.Keys
    .Union(bar.Keys)
    .Select(
        key => {
            int fval = 0, bval = 0;

            foo.TryGetValue(key, out fval);
            bar.TryGetValue(key, out bval);

            return new KeyValuePair(key, fval + bval);
        }
    )
    .ToDictionary(kvp => kvp.Key, kvp => kvp.Value);

At least it's (kind of?) neat.