GenerateETag

static string GenerateETag(DateTime lastModified,DateTime now) {
        long num = lastModified.ToFileTime();
        long num2 = now.ToFileTime();
        string str = num.ToString("X8",CultureInfo.InvariantCulture);
        if((num2 - num) <= 0x1c9c380L) {
            return ("W/\"" + str + "\"");
        }
        return ("\"" + str + "\"");
    }