IPersistStorage::InitNew - OLE Programmer's Reference (ole.hlp)

IPersistStorage::InitNew

Initializes a new storage object.

HRESULT InitNew(

IStorage *pStg	//Points to the new storage object
);

Parameter
pStg

[in]Points to the new storage object to initialize and use. The container creates a nested storage object in its storage object (see IStorage::CreateStorage). Then, the container calls the WriteClassStg function to initialize the new storage object with the component object class identifier (CLSID).

Return Values
S_OK

The new storage object was successfully initialized.

CO_E_ALREADYINITIALIZED

The component object has already been initialized by a previous call to either the IPersistStorage::Load method or the IPersistStorage::InitNew method.

E_OUTOFMEMORY

The storage object was not initialized due to a lack of memory.

E_FAIL

The storage object was not initialized due to some reason besides a lack of memory.

Comments
A container application can call this method when it needs to create a new object, for example, with an InsertObject command.

An object that uses the IPersistStorage interface must have access to a valid IStorage instance at all times while it is running. This includes the time just after the object has been created but before it has been made persistent. The object's container must provide the object with access to an IStorage instance during this time by calling IPersistStorage::InitNew. Depending on the container's state, a temporary file might need to be created for this purpose.

If the object wants to retain the IStorage instance, it must call IUnknown::AddRef to increment its reference count.

After the call to IPersistStorage::InitNew, the component object is in either the loaded or running state. For example, if the object class has an in-process server, the object will be in the running state. However, if the object uses the default handler, the container's call to InitNew only invokes the handler's implementation which does not run the component object. Later if the container runs the component object, the handler calls the IPersistStorage::InitNew method for the object.

Notes to Callers
Rather than calling IPersistStorage::InitNew directly, you typically call the OleCreate helper function which performs the following steps:

Calls the CoCreateInstance function to create an instance of the object class
Queries the new instance for the IPersistStorage interface
Calls the IPersistStorage::InitNew method to initialize the component object

The container application should cache the PersistStorage interface for the object for use in later operations on the object.

Notes to Implementors
An implementation of IPersistStorage::InitNew should initialize the component object to its default state. In particular, your implementation should perform the following steps to initialize the storage object:

Pre-open and cache the pointers to any streams or storages that the component will need to save itself to this storage.
Call IPersistStorage::AddRef and cache the passed in storage pointer.
Call the WriteFmtUserTypeStg function to write the native clipboard format and user type string for the component object to the storage object.
Set the dirty flag for the component object.

The first two steps are particularly important for ensuring that the component object can save itself in low memory situations. By pre-opening the necessary streams, the component object can guarantee that a save operation to this storage object will not fail due to insufficient memory.

Your implementation of this method should return the CO_E_ALREADYINITIALIZED error code if it receives a call to either the IPersistStorage::InitNew method or the IPersistStorage::Load method after it is already initialized.

See Also
IPersistStorage::Load, OleCreate, WriteFmtUserTypeStg

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