// PropertyName should be a valid time string. This is made sure by the IsValid property.
// It can also be empty or ISO. In this case, we default to sortable date times:
// https://docs.microsoft.com/en-us/dotnet/api/system.globalization.datetimeformatinfo.sortabledatetimepattern
private string FormatMetadataInternal(FileMetadata metadata)
{
if (string.IsNullOrWhiteSpace(PropertyName) || PropertyName.ToUpperInvariant() == "ISO")
{
// SortableDateTimePattern is the same for all cultures. We can use the invariant culture.
return(metadata.Timestamp.ToString(DateTimeFormatInfo.InvariantInfo.SortableDateTimePattern));
}
return(metadata.Timestamp.ToString(PropertyName));
}
