Access system fields
Version: 10.4
You can use the Sitecore.FieldIDs class to access system fields. For example, to access the archive date field of the /Sitecore/Content/Home/Sample item in the Master database:
RequestResponse
Sitecore.Data.Database master = Sitecore.Configuration.Factory.GetDatabase("master");
Sitecore.Data.Items.Item sample = master.GetItem("/sitecore/content/home/sample");
Sitecore.Data.Fields.DateField archiveField =
sample.Fields[Sitecore.FieldIDs.ArchiveDate];
DateTime archiveWhen = archiveField.DateTime;