CDO BodyPart Fields and Streams

[This is preliminary documentation and subject to change.]

CDO for Exchange defines common interfaces for working with MIME and RFC 822 message headers. These common interfaces are consistent with other non-messaging data-centric interfaces such the ADO. Each interface defines an ADO Fields collection and access to the body part’s associated content stream. Each interface is defined through an ADO Stream object. The following illustration , list an attached HTML page, showing the relationship of the Fields collection and the various streams associated with a body part.

The Fields collection is comprised of ADO Field objects. Each object accommodates a name/value pair that defines an aspect of the body part or message. By convention, the names of these properties are comprised of a URI prefix and a name. This convention guarantees that each property is rendered globally and unique within the scope of the associated namespace.

Each body part that is not a multipart has an associated content stream. You can request the stream in either decoded or encoded format. This stream contains the raw material of the body part. For example, a body part with a content-type "application/msword" would have a content stream containing a binary word file (.doc). When returned decoded, the stream contains the file as a series of bits, just as if it were on the file system. When the encoded stream is requested, the binary information is encoded using the process specified by the Content-Transfer-Encoding header field for the body part.