How to get Uri.EscapeDataString to comply with RFC 3986

Question

The Uri class defaults to RFC 2396. For OpenID and OAuth, I need Uri escaping consistent with RFC 3986.

From the System.Uri class documentation:

Answer 1

Having not been able to get Uri.EscapeDataString to take on RFC 3986 behavior, I wrote my own RFC 3986 compliant escaping method. It leverages Uri.EscapeDataString, and then 'upgrades' the escaping to RFC 3986 compliance.

/// 

/// The set of characters that are unreserved in RFC 2396 but are NOT unreserved in RFC 3986.
/// 
private static readonly string[] UriRfc3986CharsToEscape = new[] { "!", "*", "'", "(", ")" };

/// 

/// Escapes a string according to the URI data string rules given in RFC 3986.
/// 
/// The value to escape.
/// The escaped value.
/// 
/// The  method is supposed to take on
/// RFC 3986 behavior if certain elements are present in a .config file.  Even if this
/// actually worked (which in my experiments it doesn't), we can't rely on every
/// host actually having this configuration element present.
/// 
internal static string EscapeUriDataStringRfc3986(string value) {
    // Start with RFC 2396 escaping by calling the .NET method to do the work.
    // This MAY sometimes exhibit RFC 3986 behavior (according to the documentation).
    // If it does, the escaping we do that follows it will be a no-op since the
    // characters we search for to replace can't possibly exist in the string.
    StringBuilder escaped = new StringBuilder(Uri.EscapeDataString(value));

    // Upgrade the escaping to RFC 3986, if necessary.
    for (int i = 0; i < UriRfc3986CharsToEscape.Length; i++) {
        escaped.Replace(UriRfc3986CharsToEscape[i], Uri.HexEscape(UriRfc3986CharsToEscape[i][0]));
    }

    // Return the fully-RFC3986-escaped string.
    return escaped.ToString();
}