public static bool NotModifiedSince(this IRequest req, DateTime? lastModified)
{
if (lastModified != null)
{
var ifModifiedSince = req.Headers[HttpHeaders.IfModifiedSince];
if (ifModifiedSince != null)
{
DateTime modifiedSinceDate;
if (DateTime.TryParse(ifModifiedSince, new DateTimeFormatInfo(), DateTimeStyles.RoundtripKind, out modifiedSinceDate))
return modifiedSinceDate <= lastModified.Value.ToUniversalTime();
}
}
return false;
}