Class 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.

Inheritance

object

ImapSearchCriteria

Inherited Members

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

object.GetType()

Namespace: DRIT.Mail.Rfc.Imap

Assembly: DRIT.Mail.dll

Syntax

public sealed class ImapSearchCriteria

Methods

View Source

All()

Matches all messages (ALL).

Declaration

public ImapSearchCriteria All()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

And(ImapSearchCriteria, ImapSearchCriteria)

Combines two criteria with a logical AND. In IMAP, AND is implicit when multiple keys are listed, so this concatenates the two criteria's terms.

Declaration

public static ImapSearchCriteria And(ImapSearchCriteria a, ImapSearchCriteria b)

Parameters

Type	Name	Description
ImapSearchCriteria	a	The first criteria.
ImapSearchCriteria	b	The second criteria.

Returns

Type	Description
ImapSearchCriteria	A new criteria representing `a AND b`.

View Source

Answered()

Matches messages with the \Answered flag set.

Declaration

public ImapSearchCriteria Answered()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Bcc(string)

Matches messages bcc'd to the specified address (BCC).

Declaration

public ImapSearchCriteria Bcc(string address)

Parameters

Type	Name	Description
string	address	The address to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Before(DateTimeOffset)

Matches messages whose internal date is before the specified date (BEFORE).

Declaration

public ImapSearchCriteria Before(DateTimeOffset date)

Parameters

Type	Name	Description
DateTimeOffset	date	The date threshold (exclusive).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Body(string)

Matches messages whose body contains the specified text (BODY).

Declaration

public ImapSearchCriteria Body(string text)

Parameters

Type	Name	Description
string	text	The text to match in the body.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Cc(string)

Matches messages cc'd to the specified address (CC).

Declaration

public ImapSearchCriteria Cc(string address)

Parameters

Type	Name	Description
string	address	The address to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Create()

Creates a new empty search criteria builder.

Declaration

public static ImapSearchCriteria Create()

Returns

Type	Description
ImapSearchCriteria	A new ImapSearchCriteria instance.

View Source

Deleted()

Matches messages with the \Deleted flag set.

Declaration

public ImapSearchCriteria Deleted()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Draft()

Matches messages with the \Draft flag set.

Declaration

public ImapSearchCriteria Draft()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Flagged()

Matches messages with the \Flagged flag set.

Declaration

public ImapSearchCriteria Flagged()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

From(string)

Matches messages from the specified address (FROM).

Declaration

public ImapSearchCriteria From(string address)

Parameters

Type	Name	Description
string	address	The address to match (substring match server-side).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Header(string, string)

Matches messages with the specified header value (HEADER).

Declaration

public ImapSearchCriteria Header(string name, string value)

Parameters

Type	Name	Description
string	name	The header name (e.g. `Message-ID`).
string	value	The header value to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Keyword(string)

Matches messages with the specified user-defined keyword set (KEYWORD).

Declaration

public ImapSearchCriteria Keyword(string keyword)

Parameters

Type	Name	Description
string	keyword	The keyword (e.g. `$Junk`).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Larger(long)

Matches messages larger than the specified size in bytes (LARGER).

Declaration

public ImapSearchCriteria Larger(long size)

Parameters

Type	Name	Description
long	size	The size threshold in bytes (exclusive).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

New()

Matches messages that are new (recent and unseen) — NEW.

Declaration

public ImapSearchCriteria New()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Not(ImapSearchCriteria)

Negates a criteria (NOT). The operand is parenthesized if it contains multiple terms (implicit AND).

Declaration

public static ImapSearchCriteria Not(ImapSearchCriteria a)

Parameters

Type	Name	Description
ImapSearchCriteria	a	The criteria to negate.

Returns

Type	Description
ImapSearchCriteria	A new criteria representing `NOT a`.

View Source

Old()

Matches messages that are old (not recent) — OLD.

Declaration

public ImapSearchCriteria Old()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

On(DateTimeOffset)

Matches messages whose internal date is the specified date (ON).

Declaration

public ImapSearchCriteria On(DateTimeOffset date)

Parameters

Type	Name	Description
DateTimeOffset	date	The date to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Or(ImapSearchCriteria, ImapSearchCriteria)

Combines two criteria with a logical OR (OR). Each operand is parenthesized if it contains multiple terms (implicit AND).

Declaration

public static ImapSearchCriteria Or(ImapSearchCriteria a, ImapSearchCriteria b)

Parameters

Type	Name	Description
ImapSearchCriteria	a	The first criteria.
ImapSearchCriteria	b	The second criteria.

Returns

Type	Description
ImapSearchCriteria	A new criteria representing `a OR b`.

View Source

Recent()

Matches messages with the \Recent flag set.

Declaration

public ImapSearchCriteria Recent()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Seen()

Matches messages with the \Seen flag set.

Declaration

public ImapSearchCriteria Seen()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

SentBefore(DateTimeOffset)

Matches messages whose Date header is before the specified date (SENTBEFORE).

Declaration

public ImapSearchCriteria SentBefore(DateTimeOffset date)

Parameters

Type	Name	Description
DateTimeOffset	date	The date threshold (exclusive).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

SentOn(DateTimeOffset)

Matches messages whose Date header is the specified date (SENTON).

Declaration

public ImapSearchCriteria SentOn(DateTimeOffset date)

Parameters

Type	Name	Description
DateTimeOffset	date	The date to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

SentSince(DateTimeOffset)

Matches messages whose Date header is on or after the specified date (SENTSINCE).

Declaration

public ImapSearchCriteria SentSince(DateTimeOffset date)

Parameters

Type	Name	Description
DateTimeOffset	date	The date threshold (inclusive).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Since(DateTimeOffset)

Matches messages whose internal date is on or after the specified date (SINCE).

Declaration

public ImapSearchCriteria Since(DateTimeOffset date)

Parameters

Type	Name	Description
DateTimeOffset	date	The date threshold (inclusive).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Smaller(long)

Matches messages smaller than the specified size in bytes (SMALLER).

Declaration

public ImapSearchCriteria Smaller(long size)

Parameters

Type	Name	Description
long	size	The size threshold in bytes (exclusive).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Subject(string)

Matches messages with the specified subject text (SUBJECT).

Declaration

public ImapSearchCriteria Subject(string text)

Parameters

Type	Name	Description
string	text	The subject text to match (substring match server-side).

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Text(string)

Matches messages whose header or body contains the specified text (TEXT).

Declaration

public ImapSearchCriteria Text(string text)

Parameters

Type	Name	Description
string	text	The text to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

To(string)

Matches messages addressed to the specified address (TO).

Declaration

public ImapSearchCriteria To(string address)

Parameters

Type	Name	Description
string	address	The address to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

ToCommandString()

Returns the SEARCH argument string (e.g. FROM "alice" SINCE 1-Jan-2026 UNSEEN).

Declaration

public string ToCommandString()

Returns

Type	Description
string	The command string for this criteria.

View Source

Uid(ImapMessageSet)

Matches messages in the specified UID set (UID).

Declaration

public ImapSearchCriteria Uid(ImapMessageSet set)

Parameters

Type	Name	Description
ImapMessageSet	set	The UID set to match.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Unanswered()

Matches messages without the \Answered flag set.

Declaration

public ImapSearchCriteria Unanswered()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Undeleted()

Matches messages without the \Deleted flag set.

Declaration

public ImapSearchCriteria Undeleted()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Unflagged()

Matches messages without the \Flagged flag set.

Declaration

public ImapSearchCriteria Unflagged()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Unkeyword(string)

Matches messages without the specified user-defined keyword (UNKEYWORD).

Declaration

public ImapSearchCriteria Unkeyword(string keyword)

Parameters

Type	Name	Description
string	keyword	Specifies the keyword value.

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.

View Source

Unseen()

Matches messages without the \Seen flag set.

Declaration

public ImapSearchCriteria Unseen()

Returns

Type	Description
ImapSearchCriteria	This criteria instance for chaining.