private static string GetParamList<T>(object values)
{
    if (values.GetType().Equals(typeof(string[])) )
    {
        string[] res = (string[])values;
        if (values.GetType().Equals(typeof(string[])))
        {
            for (int i = 0; i < res.Length; i++)
            {
                if (!res[i].ToString().StartsWith("""))
                {
                    res[i] = string.Format(""{0}"", res[i]);
                }
            }
        }
        return string.Join(",", res);
    }
    else if (values.GetType().Equals(typeof(string)))
    {
        return string.Format(""{0}"", values);
    }
    else// array of numbers:
    {
        string[] res = ((T[])values).Select(x => x.ToString()).ToArray<string>();
        return string.Join(",", res);
    }
}

private static string dictToJson(Dictionary<string, object> data)
{
    List<string> entries = new List<string>();
    foreach (var entry in data)
    {
        Type T = entry.Value.GetType();
        entries.Add(string.Format(""{0}": {1}", entry.Key, GetParamList<T>(entry.Value)));
    }
    return "{" + string.Join(",", entries.ToArray<string>()) + "}";
}