System.Net.HttpUtility.GetChars C# (CSharp) Method

		static char [] GetChars (MemoryStream b, Encoding e)
		{
			return e.GetChars (b.GetBuffer (), 0, (int) b.Length);
		}

        public static string UrlDecode(string s, Encoding e)
        {
            if (s == null)
            {
                return(null);
            }
            if (s.IndexOf('%') == -1 && s.IndexOf('+') == -1)
            {
                return(s);
            }
            if (e == null)
            {
                e = Encoding.GetEncoding(28591);
            }
            StringBuilder stringBuilder = new StringBuilder();
            long          num           = (long)s.Length;
            NumberStyles  style         = NumberStyles.HexNumber;
            MemoryStream  memoryStream  = new MemoryStream();
            int           num2          = 0;

            while ((long)num2 < num)
            {
                if (s[num2] == '%' && (long)(num2 + 2) < num)
                {
                    if (s[num2 + 1] == 'u' && (long)(num2 + 5) < num)
                    {
                        if (memoryStream.Length > 0L)
                        {
                            stringBuilder.Append(HttpUtility.GetChars(memoryStream, e));
                            memoryStream.SetLength(0L);
                        }
                        stringBuilder.Append((char)int.Parse(s.Substring(num2 + 2, 4), style));
                        num2 += 5;
                    }
                    else
                    {
                        memoryStream.WriteByte((byte)int.Parse(s.Substring(num2 + 1, 2), style));
                        num2 += 2;
                    }
                }
                else
                {
                    if (memoryStream.Length > 0L)
                    {
                        stringBuilder.Append(HttpUtility.GetChars(memoryStream, e));
                        memoryStream.SetLength(0L);
                    }
                    if (s[num2] == '+')
                    {
                        stringBuilder.Append(' ');
                    }
                    else
                    {
                        stringBuilder.Append(s[num2]);
                    }
                }
                num2++;
            }
            if (memoryStream.Length > 0L)
            {
                stringBuilder.Append(HttpUtility.GetChars(memoryStream, e));
            }
            return(stringBuilder.ToString());
        }