This wrapper function encodes string for use in URI. The function is necessary because Mono framework doesn't support HttpUtility.UrlEncode() method and Uri.EscapeDataString() method doesn't support long strings, so a loop is required. By the way HttpUtility.UrlDecode() is supported by Mono, and a functions pair Uri.EscapeDataString()/HttpUtility.UrlDecode() is commonly recommended for encoding/decoding. Although there is another trouble with Uri.EscapeDataString(): prior to .NET 4.5 it doesn't support RFC 3986, only RFC 2396.

public static string UrlEncode(
	string str
)