public const string SafeUrlCharacters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_.~";

        /// <summary>
        /// URL-encodes a string for use with OAuth.
        /// </summary>
        /// <param name="toEncode">
        /// The string to encode.
        /// </param>
        /// <returns>
        /// A URL-encoded string where all of the encoded characters are upper-case.
        /// </returns>
        /// <remarks>