Accessing HTTP Multipart Data 

Some HTTP requests keep their data not in their own body part, but in various segments known as multiparts. Multiparts consist of their own HTTP (sub-)header and (sub-)body. Multiparts can be accessed via the interface IF_HTTP_ENTITY, which consists of the interfaces IF_HTTP_REQUEST and IF_HTTP_RESPONSE. The methods ADD_MULTIPART(), GET_MULTIPART() and NUM_MULTIPARTS() of the interface IF_HTTP_ENTITY provide the functionality for navigating in the multipart segment tree.

This is described in IF_HTTP_ENTITY.