Namespace DRIT.Mail.Rfc.Imap

Classes

ImapAuthenticationException

Thrown when IMAP authentication fails (e.g. a NO response to LOGIN or AUTHENTICATE), when no authentication mechanism can be negotiated, or when authentication is refused over an unencrypted connection.

ImapClient

Receives and manages mail via IMAP4rev1/IMAP4rev2 (RFC 9051). One instance maintains a single connection. Not thread-safe; use one instance per thread. IDLE runs on a background thread and must not be combined with other commands on the same instance.

ImapClientOptions

Configuration for ImapClient. Mutable during construction; set all properties before calling Connect().

ImapException

The base exception type for all IMAP errors.

ImapExistsEventArgs

Event data for the MessageArrived event, raised when the server pushes * N EXISTS indicating the mailbox message count has increased.

ImapExpungeEventArgs

Event data for the MessageExpunged event, raised when the server pushes * N EXPUNGE indicating a message was permanently removed.

ImapFlagsChangedEventArgs

Event data for the FlagsChanged event, raised when the server pushes * N FETCH (FLAGS (...)) during IDLE, indicating that a message's flags have changed.

ImapFolder

Information about a single IMAP mailbox/folder as returned by LIST or LSUB (RFC 9051 §6.3.8–§6.3.9). Immutable.

ImapIdleActiveException

Thrown when a command is issued on an ImapClient while an IDLE session is active. The caller must Stop the IDLE session before issuing other commands.

ImapIdleErrorEventArgs

Event data for the Error event, raised when the transport or protocol encounters an error during IDLE.

ImapIdleSession

Represents an active IMAP IDLE session (RFC 2177). Created by StartIdle(). The session runs a background thread that reads server-pushed untagged responses and raises events. Callers must marshal event handlers to their own thread. To issue any other command on the ImapClient, call Stop() (or Dispose()) first.

ImapMailbox

The result of a SELECT or EXAMINE command (RFC 9051 §6.3.1). Immutable. Contains the mailbox metadata from untagged responses.

ImapMailboxNotSelectedException

Thrown when a command that requires a selected mailbox (FETCH, STORE, SEARCH, COPY, EXPUNGE) is issued while no mailbox is selected.

ImapMailboxStatus

The result of an IMAP STATUS command (RFC 9051 §6.3.10). Immutable. Contains mailbox counts without selecting the mailbox.

ImapMessageInfo

Information about a single message in an IMAP mailbox, as returned by FETCH (RFC 9051 §6.4.5). Immutable. Only the fields requested in ImapFetchOptions are populated; others are null/zero.

ImapMessageSet

Represents a set of IMAP messages addressed by sequence number or UID (RFC 9051 §9). Produces the compact command-string form with range collapsing (e.g. 1,2,3 → 1:3).

ImapProtocolException

Thrown when the IMAP server returns a NO or BAD response, or a malformed reply, or when a required extension is not advertised.

ImapRecentEventArgs

Event data for the RecentChanged event, raised when the server pushes * N RECENT.

ImapSearchCriteria

A fluent builder for IMAP SEARCH criteria (RFC 9051 §6.4.4). Produces the SEARCH argument string (e.g. FROM "alice" SINCE 1-Jan-2026 UNSEEN). Multiple criteria chained on the same instance are implicitly ANDed (the IMAP default). Use Or(ImapSearchCriteria, ImapSearchCriteria) / Not(ImapSearchCriteria) for explicit boolean logic.

ImapServerCapabilities

Extensions advertised by the IMAP server in its CAPABILITY response (RFC 9051 §6.1.1). Immutable.

ImapTimeoutException

Thrown when a read or write operation times out before the IMAP server responds.