Most elegant way to convert string array into a dictionary of strings

Question

Is there a built-in function for converting a string array into a dictionary of strings or do you need to do a loop here?

Answer 1

IMO, When we say an Array we are talking about a list of values that we can get a value with calling its index (value => array[index]), So a correct dictionary is a dictionary with a key of index.

And with thanks to @John Skeet, the proper way to achieve that is:

var dictionary = array
    .Select((v, i) => new {Key = i, Value = v})
    .ToDictionary(o => o.Key, o => o.Value);

---

Another way is to use an extension method like this:

public static Dictionary<int, T> ToDictionary<T>(this IEnumerable<T> array)
{
    return array
        .Select((v, i) => new {Key = i, Value = v})
        .ToDictionary(o => o.Key, o => o.Value);
}

Answer 2

I'll assume that the question has to do with arrays where the keys and values alternate. I ran into this problem when trying to convert redis protocol to a dictionary.

private Dictionary<T, T> ListToDictionary<T>(IEnumerable<T> a)
{
    var keys = a.Where((s, i) => i % 2 == 0);
    var values = a.Where((s, i) => i % 2 == 1);
    return keys
        .Zip(values, (k, v) => new KeyValuePair<T, T>(k, v))
        .ToDictionary(kv => kv.Key, kv => kv.Value);
}