MapiFileDescW structure (mapi.h)

A MapiFileDescW structure contains information about a file containing a message attachment stored as a temporary file. That file can contain a static OLE object, an embedded OLE object, an embedded message, and other types of files.

Syntax

typedef struct {
  ULONG ulReserved;
  ULONG flFlags;
  ULONG nPosition;
  PWSTR lpszPathName;
  PWSTR lpszFileName;
  PVOID lpFileType;
} MapiFileDescW, *lpMapiFileDescW;

Members

ulReserved

Type: ULONG

Reserved; must be 0.

flFlags

Type: ULONG

Bitmask of attachment flags. The following flags can be set.

Value	Meaning
MAPI_OLE 0x00000001	The attachment is an OLE object. If MAPI_OLE_STATIC is also set, the attachment is a static OLE object. If MAPI_OLE_STATIC is not set, the attachment is an embedded OLE object.
MAPI_OLE_STATIC 0x00000002	The attachment is a static OLE object.

 

If neither flag is set, the attachment is treated as a data file.

nPosition

Type: ULONG

An integer used to indicate where the attachment is rendered in the message text. The message text is stored in the NoteText member of the MapiMessageW structure, and the integer is used as an index to identify a specific character in the message string, NoteText[nPosition], that is replaced by the attachment.

A value of -1 (0xFFFFFFFF) means the attachment position is not indicated and the client application must provide a way for the user to access the attachment.

lpszPathName

Type: PWSTR

Pointer to the fully qualified path of the attached file. This path should include the disk drive letter and directory name.

lpszFileName

Type: PWSTR

Pointer to the filename of the attachment as seen by the recipient. The filename that is seen by the recipient may differ from the filename in the lpszPathName member if temporary files are being used.

If the lpszFileName member is empty or NULL, the filename from lpszPathName is used.

lpFileType

Type: PVOID

Pointer to the attachment file type, which can be represented with a MapiFileTagExt structure.

A value of NULL indicates an unknown file type or a file type determined by the operating system.

Remarks

Simple MAPI works with three kinds of embedded attachments:

• Data file attachments
• Editable OLE object file attachments
• Static OLE object file attachments

Data file attachments are simply data files. OLE object file attachments are OLE objects that are displayed in the message text. If the OLE attachment is editable, the recipient can double-click it and its source application will be started to handle the edit session. If the OLE attachment is static, the object cannot be edited. The flag set in the flFlags member of the MapiFileDescW structure determines the kind of a particular attachment. Embedded messages can be identified by a .MSG extension in the lpszFileName member.

OLE object files are file representations of OLE object streams. The client application can re-create an OLE object from the file by calling the OLE function OleLoadFromStream with an OLESTREAM object that reads the file contents. If an OLE file attachment is included in an outbound message, the OLE object stream should be written directly to the file used as the attachment.

When using the MapiFileDescW member nPosition, the client application should not place two attachments in the same location. Client applications might not display file attachments at positions beyond the end of the message text.

Requirements

Requirement	Value
Minimum supported client	Windows 8 [desktop apps only]
Minimum supported server	Windows Server 2012 [desktop apps only]
Header	mapi.h

See also

MAPISendMailW

MapiFileDesc

MapiMessageW