public static string ToLiteral(
	string s,
	Encoding charsetEncoding,
	Encoding requestEncoding
)

Public Shared Function ToLiteral ( 
	s As String,
	charsetEncoding As Encoding,
	requestEncoding As Encoding
) As String

Parameters

s

Type: SystemString
The text string to convert.

charsetEncoding

Type: System.TextEncoding
Denotes the charset of the resulting string. If a null reference (Nothing in Visual Basic), UTF8 is used. Must match the charset specified in Search(Boolean, String, String) method call.

requestEncoding

Type: System.TextEncoding
Must match RequestEncoding value. If a null reference, DefaultEncoding is used (RequestEncoding uses the same default value).

Return Value

You'll typically use this method to build search string in non-ASCII charset when the IMAP server is Gmail.

If you're using UTF-8 charset for search strings and you never changed RequestEncoding from its default value, use ToLiteral(String) overload instead.

Note
This method produces literals in very efficient LITERAL+ syntax. Gmail does not advertize the support of LITERAL+ extension but it's actually supported.

Reference