Known
Definition
Assembly: OpenDiscoverSDK.Interfaces (in OpenDiscoverSDK.Interfaces.dll) Version: 2026.2.6.0 (2026.02.06)
public class KnownMetadataAttribute : AttributeRemarks
Open Discover® SDK has over 1350 known metadata fields that can be extracted from all supported file formats. These metadata fields are grouped by object type (see KnownBooleanMetadataFields, KnownDateTimeMetadataFields, KnownDoubleMetadataFields, KnownInt32MetadataFields, KnownInt64MetadataFields, and KnownStringMetadataFields). In addition to these known formats, the SDK also extracts user defined custom metadata fields but since these fields can be named anything the document author desires, they are not covered in the known fields.
This attribute can help sort these large sets of metadata fields by major document classification (see KnownMetadataHelper class).
NOTE: Many metadata fields apply to multiple document classifications so more than one property on this attribute can be true. Also, some known metadata fields might not have any attribute property set to true because the associated document format does not fall under any classifications defined by this attribute.
Constructors
| KnownMetadataAttribute | Constructor. |
Properties
| IsArchiveType | Gets or sets whether this metadata field is associated with archive or media image metadata (e.g., 7Z, ZIP, RAR, etc). |
| IsDocumentStoreType | Gets or sets whether this metadata field is associated with a document store metadata (e.g., Domino DXL document database (.xml)). |
| IsEmailMapiType | Gets or sets whether this metadata field is associated with Outlook/Exchange MAPI email .msg object metadata. See email settings class ExtractAllKnownOutlookMAPIProperties to extract all known MAPI properties. |
| IsEmailType | Gets or sets whether this metadata field is associated with email metadata (e.g., Microsoft Outlook, MIME, DXL, iCalendar, etc). These are email format common metadata fields. See IsEmailMapiType for only Outlook/Exchange email object MAPI properties. |
| IsHtmlType | Gets or sets whether this metadata field is associated with HTML metadata. |
| IsImageType | Gets or sets whether this metadata field is associated with image metadata (e.g., JPG, PNG, GIF, TIFF, etc). |
| IsMailStoreType | Gets or sets whether this metadata field is associated with mail store metadata (e.g., PST, OST, MBOX, etc). |
| IsMessagingStoreType | Gets or sets whether this metadata field is associated with messaging store metadata (e.g., Slack export, WhatsApp export, etc). |
| IsMessagingType | Gets or sets whether this metadata field is associated with messaging metadata (e.g., Microsoft Teams/Skype, Slack, etc). |
| IsMultiMediaType | Gets or sets whether this metadata field is associated with multimedia metadata (e.g., music and video formats). |
| IsOfficeType | Gets or sets whether this metadata field is associated with common office document metadata (e.g., Microsoft Office, Libre/Apache Office, PDF, etc). |
| IsOther | Gets or sets whether this metadata field is associated with a format that does not belong to a known format classification. |
| IsReserved | RESERVED metadata field. |
| TypeId | When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute) |
Methods
| Equals | Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute) |
| GetHashCode | Returns the hash code for this instance. (Inherited from Attribute) |
| GetType | Gets the Type of the current instance. (Inherited from Object) |
| IsDefaultAttribute | When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute) |
| Match | When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute) |
| ToString | Returns a string that represents the current object. (Inherited from Object) |