DMUS_OBJECTDESC

The DMUS_OBJECTDESC structure is used to describe a DirectMusic object. It is passed to the IDirectMusicLoader::GetObject method to identify the object that the loader should retrieve from storage. Information about an object is retrieved in this structure by the IDirectMusicLoader::EnumObject and IDirectMusicObject::GetDescriptor methods.

typedef struct _DMUS_OBJECTDESC {
    DWORD         dwSize;
    DWORD         dwValidData;
    GUID          guidObject;
    GUID          guidClass;
    FILETIME      ftDate;
    DMUS_VERSION  vVersion;
    WCHAR         wszName[DMUS_MAX_NAME];
    WCHAR         wszCategory[DMUS_MAX_CATEGORY];
    WCHAR         wszFileName[DMUS_MAX_FILENAME];
    LONGLONG      llMemLength;
    PBYTE         pbMemData;
} DMUS_OBJECTDESC, *LPDMUS_OBJECTDESC;

Members

dwSize

Size of the structure, in bytes. This member must be initialized to sizeof(DMUS_OBJECTDESC) before the structure is passed to any method.

dwValidData

Flags describing which members are valid and giving further information about some members. The following values are defined:

DMUS_OBJ_OBJECT

The guidObject member is valid.

DMUS_OBJ_CLASS

The guidClass member is valid.

DMUS_OBJ_NAME

The wszName member is valid.

DMUS_OBJ_CATEGORY

The wszCategory member is valid.

DMUS_OBJ_FILENAME

The wszFileName member is valid.

DMUS_OBJ_FULLPATH

The wszFileName member contains the full path. If this flag is set, the loader assumes that wszFileName is valid even if DMUS_OBJ_FILENAME has not been set.

DMUS_OBJ_MEMORY

The object is in memory, and llMemLength and pbMemData are valid.

DMUS_OBJ_URL

The wszFileName member contains a URL. (URLs are not currently supported by the DirectMusic loader.)

DMUS_OBJ_VERSION

The vVersion member is valid.

DMUS_OBJ_DATE

The ftDate member is valid.

DMUS_OBJ_LOADED

The object is currently loaded in memory.

guidObject

Unique identifier for this object.

guidClass

Unique identifier for the class of object. All the standard objects have defined identifiers consisting of "CLSID_" plus the name of the object. For example, a segment object is identified as CLSID_DirectMusicSegment. See the defines in the Dmusici.h header file.

ftDate

Date that the object was last edited.

vVersion

DMUS_VERSION structure containing version information.

wszName

Name of the object.

wszCategory

Category for the object.

wszFileName

File path. If DMUS_OBJ_FULLPATH is set, this is the full path; otherwise, it is the file name.

llMemLength

Size of data in memory.

pbMemData

Data in memory.

Remarks

At least one of wszName, guidObject, and wszFileName must be filled with valid data to retrieve the object by using the IDirectMusicLoader::GetObject method.

The name and category strings use 16-bit characters in the WCHAR format, not 8-bit ANSI chars. Be sure to convert as appropriate. You can use the C-library mbstowcs functionto convert from multibyte to Unicode and the wcstombs functionto convert from Unicode back to multibyte.

Requirements

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in dmusici.h.

See Also

DirectMusic Loader