IMAPIFolder::SetReadFlags

lpMsgList

[in] A pointer to an array of ENTRYLIST structures that identify the message or messages that have read flags to set or clear. If lpMsgList is set to NULL, the read flags for all the folder's messages are set or cleared.

ulUIParam

[in] A handle to the parent window of the progress indicator. The ulUIParam parameter is ignored unless the MESSAGE_DIALOG flag is set in the ulFlags parameter.

lpProgress

[in] A pointer to a progress object that displays a progress indicator. If NULL is passed in lpProgress, the message store provider displays a progress indicator by using MAPI's implementation. The lpProgress parameter is ignored unless the MESSAGE_DIALOG flag is set in ulFlags.

ulFlags

[in] A bitmask of flags that controls the setting of a message's read flag and the processing of read reports. The following flags can be set:

CLEAR_READ_FLAG

The MSGFLAG_READ flag should be cleared in PR_MESSAGE_FLAGS and a read report should not be sent.

CLEAR_NRN_PENDING

The MSGFLAG_NRN_PENDING flag should be cleared in PR_MESSAGE_FLAGS and an unread report should not be sent.

CLEAR_RN_PENDING

The MSGFLAG_RN_PENDING flag should be cleared in PR_MESSAGE_FLAGS and a read report should not be sent.

GENERATE_RECEIPT_ONLY

A read report should be sent if one is pending, but there should be no change in the state of the MSGFLAG_READ flag.

MAPI_DEFERRED_ERRORS

Allows SetReadFlags to return successfully, possibly before the operation has completed.

MESSAGE_DIALOG

Displays a progress indicator while the operation proceeds.

SUPPRESS_RECEIPT

A pending read report should be canceled if a read report had been requested and this call changes the state of the message from unread to read. If this call does not change the state of the message, the message store provider can ignore this flag.

S_OK

The read flag for the specified message or messages was successfully set or cleared.

MAPI_E_NO_SUPPRESS

The message store provider does not support the suppression of read reports.

MAPI_E_INVALID_PARAMETER

One of the following incompatible combinations of flags is set in the ulFlags parameter:

• SUPPRESS_RECEIPT | CLEAR_READ_FLAG

• SUPPRESS_RECEIPT | CLEAR_READ_FLAG | GENERATE_RECEIPT_ONLY

• CLEAR_READ_FLAG | GENERATE_RECEIPT_ONLY

MAPI_W_PARTIAL_COMPLETION

The call succeeded, but not all of the messages were successfully processed. When this warning is returned, the call should be handled as successful. To test for this warning, use the HR_FAILED macro. For more information, see Using Macros for Error Handling.

The IMAPIFolder::SetReadFlags method sets or clears the MSGFLAG_READ flag in the PR_MESSAGE_FLAGS property of one or more of the folder's messages. Setting the MSGFLAG_READ flag marks a message as read, which does not necessarily indicate that the intended recipient has actually read the message.

SetReadFlags also manages the sending of read reports.

The read flag cannot be changed for the following:

• Messages that do not exist.

• Messages that have been moved elsewhere.

• Messages that are open with read/write permission.

• Messages that are currently submitted.

You can decide not to support the sending of read reports and the request to suppress read reports. To avoid suppressing a read report, return MAPI_E_NO_SUPPRESS when SetReadFlags is called with SUPPRESS_RECEIPT set in the ulFlags parameter.

When the lpMsgList parameter points to more than one message, perform the operation as completely as possible for each message. Do not stop the operation prematurely unless a failure occurs that is beyond your control, such as running out of memory, running out of disk space, or corruption in the message store.

If none of the flags are set in the ulFlags parameter, the following rules apply:

• If MSGFLAG_READ is already set, do nothing.

• If MSGFLAG_READ is not set, set it immediately and send any pending read reports if the PR_READ_RECEIPT_REQUESTED (PidTagReadReceiptRequested) property is set.

When the SUPPRESS_RECEIPT flag is set, the following rules apply:

• If MSGFLAG_READ is already set, do nothing.

• If MSGFLAG_READ is not set, set it and cancel any pending read reports.

When the CLEAR_READ_FLAG flag is set, clear the MSGFLAG_READ flag in each message's PR_MESSAGE_FLAGS property and do not send any read reports.

When the GENERATE_RECEIPT_ONLY flag is set, send any pending read reports. Do not set or clear MSGFLAG_READ.

When both the SUPPRESS_RECEIPT and GENERATE_RECEIPT_ONLY flags are set, set PR_READ_RECEIPT_REQUESTED to FALSE if it is set and do not send a read report.

Expect these return values under the following conditions.

When SetReadFlags is unable to complete, do not assume that no work was done. SetReadFlags might have been able to set or clear the MSGFLAG_READ flag for one or more of the messages before encountering the error.

For MFCMAPI sample code, see the following table.

Reference

Concepts