Get Dictionary key by using the dictionary value

Question

How to get the dictionary key by using the dictionary value?

when getting the value using the key its like this:

Dictionary dic =          


        

Answer 1

easy way for get one key:

    public static TKey GetKey(Dictionary dictionary, TValue Value)
    {
        List KeyList = new List(dictionary.Keys);
        foreach (TKey key in KeyList)
            if (dictionary[key].Equals(Value))
                return key;
        throw new KeyNotFoundException();
    }

and for multiples keys:

    public static TKey[] GetKeys(Dictionary dictionary, TValue Value)
    {
        List KeyList = new List(dictionary.Keys);
        List FoundKeys = new List();
        foreach (TKey key in KeyList)
            if (dictionary[key].Equals(Value))
                FoundKeys.Add(key);
        if (FoundKeys.Count > 0)
            return FoundKeys.ToArray();
        throw new KeyNotFoundException();
    }