Casting C# out parameters?

I don’t know if it is a great idea, but you could add a generic extension method:

    static bool TryGetTypedValue<TKey, TValue, TActual>(
        this IDictionary<TKey, TValue> data,
        TKey key,
        out TActual value) where TActual : TValue
    {
        if (data.TryGetValue(key, out TValue tmp))
        {
            value = (TActual)tmp;
            return true;
        }
        value = default(TActual);
        return false;
    }
    static void Main()
    {
        Dictionary<string,object> dict
            = new Dictionary<string,object>();
        dict.Add("abc","def");
        string key = "abc", value;
        dict.TryGetTypedValue(key, out value);
    }