IPropertySetStorage::Open
Opens a property
set contained in the property set storage object.
HRESULT
Open(
|
REFFMTID fmtid, |
//The format identifier of the property set to be
opened |
|
DWORD grfMode, |
//Storage mode in which property set is to be opened |
|
IPropertyStorage** ppPropStg |
//Indirect pointer to property storage object |
|
); |
|
Parameters
fmtid
[in] Format
identifier of the property set to be opened.
grfMode
[in] Access
mode in which the newly created property set is to be opened. These flags are
taken from the STGM enumeration. Flags that may be used and their meanings in
the context of this method are described in the Remarks.
ppPropStg
[in] Indirect
pointer to the IPropertyStorage interface on the requested property
storage sub-object.
Return Values
This method
supports the standard return value E_UNEXPECTED, as well as the following:
S_OK
Success.
STG_E_FILENOTFOUND
A property
set of the indicated name does not exist.
STG_E_ACCESSDENIED
The requested
access to the property storage object has been denied, or the property set is
corrupted.
STG_E_INSUFFICIENTMEMORY
There is not
sufficient memory to perform this operation.
STG_E_INVALIDPARAMETER
A parameter
is invalid.
Remarks
The mode in
which the property set is to be opened is specified in the parameter grfMode.
These flags are taken from the STGM enumeration, but, for this method,
legal values and their meanings are as follows (only certain combinations of
these flag values are legal).
|
Value |
Meaning |
|
STGM_DIRECT |
Open the
property set without an additional level of transaction nesting. This is the default
(the behavior if neither STGM_DIRECT nor STGM_TRANSACTED is specified). |
|
STGM_TRANSACTED |
Open the
property set with an additional level of transaction nesting (beyond the
transaction, if any, on this property set storage object). Transacted mode is
available only on non-simple property sets, because they use an IStorage
with a contents stream. Changes in the property set must be committed with a
call to IPropertyStorage::Commit before they are visible to the
transaction on this property set storage. |
|
STGM_READ |
Open the
property set with read access. Read permission is required on the property set
storage. |
|
STGM_WRITE |
Open the
property set with write access. Write permission is not required on the
IPropertySetStorage; however, such write permission is required for changes
in the storage to be committed. |
|
STGM_READWRITE |
Open the
property set with read-write access. Note that this flag is not the binary OR
of the values STGM_READ and STGM_WRITE. |
|
STGM_SHARE_DENY_NONE |
Subsequent openings
of the property set are not denied read or write access. Not available in
compound file implementation. |
|
STGM_SHARE_DENY_READ |
Subsequent
openings of the property set in are denied read access. Not available in
compound file implementation. |
|
STGM_SHARE_DENY_WRITE |
Subsequent
openings of the property set are denied write access. This value is typically
used to prevent making unnecessary copies of an object opened by multiple
users. If this value is not specified, a snapshot is made, whether there are subsequent
openings or not. Thus, you can improve performance by specifying this value.
Not available in compound file implementation. |
|
STGM_SHARE_EXCLUSIVE |
The
combination of STGM_SHARE_DENY_READ and STGM_SHARE_DENY_WRITE. |