Finding a value from within a List of Dictionary objects

Question

I have what can potentially be a very large list of Dictionary objects that I will need to find a particular value from a key. I can certainly do something like

foreach(Dictionary<long, string> t in Foo)
{
    if (t.TryGetValue(key, out name))
        break;
}

and this will happily iterate through Foo until it finds the key or the foreach ends.

To speed this up, I'd prefer to use a small amount of LINQ. If this was a normal list, I'd be ok, but as this is a List of Dictionary objects, I'm not too sure how it's done.

Help or advice appreciated.

Answer 1

I think you have written the most efficient version of what you want to do. Since Linq doesn't play nicely with output parameters, it will take slightly longer. But here is how you would do it:

var dict = Foo.FirstOrDefault(d => d.ContainsKey(key));
if (dict != null) { dict.TryGetValue(key, out name); }