The PR_CONVERSATION_INDEX property contains a binary value that indicates the relative position of this message within a conversation thread.
| Header file: | MAPITAGS.H |
| May be exposed by: | Message objects |
| Identifier: | 0x0071 |
| Property type: | PT_BINARY |
| Property tag: | 0x00710102 |
A conversation thread represents a series of messages and replies. The PR_CONVERSATION_INDEX property is usually implemented using concatenated time stamp values. Its use is optional, even if PR_CONVERSATION_TOPIC is set.
MAPI provides the ScCreateConversationIndex function to create or update a conversation index. The function takes the current index value as a counted byte array and returns the index value with a time stamp concatenated onto the end. A message representing a reply to another message should use ScCreateConversationIndex to update PR_CONVERSATION_INDEX.
A message store provider has the option of assuring that PR_CONVERSATION_INDEX is always set on incoming or outgoing messages. It can do this by calling ScCreateConversationIndex, either with the existing value if PR_CONVERSATION_INDEX is set or with NULL if it is not. This action should be taken before IMAPIProp::SaveChanges is called.
All messages that have the same value for PR_CONVERSATION_TOPIC can be sorted on PR_CONVERSATION_INDEX to reveal the hierarchical relationship of the messages.