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Value Name



This value type is used to identify properties that contain a character encoding of inline binary data. For example, an inline attachment of a document might be included in an iCalendar object.

Format Definition

This value type is defined by the following notation:

 binary     = *(4b-char) [b-end]
 ; A "BASE64" encoded character string, as defined by [RFC4648].

 b-end      = (2b-char "==") / (3b-char "=")

 b-char = ALPHA / DIGIT / "+" / "/"


Property values with this value type MUST also include the inline encoding parameter sequence of ";ENCODING=BASE64". That is, all inline binary data MUST first be character encoded using the "BASE64" encoding method defined in [RFC2045]. No additional content value encoding (i.e., BACKSLASH character encoding, see Section 3.3.11) is defined for this value type.

Example: The following is an example of a "BASE64" encoded binary value data:


This document was automatically converted to XHTML using an RFC to HTML converter with the original text document at the Internet Engineering Task Force web site at .  The original text document should be referred to if there are any errors or discrepancies found in this document.

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