IPersistStream::Save (Compact 2013)

Artículo
11/04/2015

3/26/2014

This method saves an object to the specified stream.

Syntax

HRESULT Save(
  IStream* pStm, 
  BOOL fClearDirty
);

Parameters

pStm
[in] IStream pointer to the stream into which the object should be saved.

fClearDirty
[in] Value that indicates whether to clear the dirty flag after the save is complete. If TRUE, the flag should be cleared. If FALSE, the flag should be left unchanged.

Return Value

The following table shows the return values for this method.

Value	Description
S_OK	The object was successfully saved to the stream.
STG_E_CANTSAVE	The object could not save itself to the stream. This error could indicate, for example, that the object contains another object that is not serializable to a stream or that an ISequentialStream::Write call returned STG_E_CANTSAVE.
STG_E_MEDIUMFULL	The object could not be saved because there is no space left on the storage device.

S_OK

The object was successfully saved to the stream.

STG_E_CANTSAVE

The object could not save itself to the stream.

This error could indicate, for example, that the object contains another object that is not serializable to a stream or that an ISequentialStream::Write call returned STG_E_CANTSAVE.

STG_E_MEDIUMFULL

The object could not be saved because there is no space left on the storage device.

Remarks

IPersistStream::Save saves an object into the specified stream and indicates whether the object should reset its dirty flag.

The seek pointer is positioned at the location in the stream at which the object should begin writing its data. The object calls the ISequentialStream::Write method to write its data.

On exit, the seek pointer must be positioned immediately past the object data. The position of the seek pointer is undefined if an error returns.

To determine whether the platform supports this interface, see Determining Supported COM APIs.

Notes to Callers

Rather than calling IPersistStream::Save directly, you typically call the OleSaveToStream helper function, which does the following:

Calls the IPersist::GetClassID method to get the object's CLSID.
Calls the WriteClassStm function to write the object's CLSID to the stream.
Calls IPersistStream::Save.

If you call these methods directly, you can write other data into the stream after the CLSID before calling IPersistStream::Save.

The OLE-provided implementation of the IPersistStream interface follows this same pattern.

Notes to Implementers

The IPersistStream::Save method does not write the CLSID to the stream. The caller is responsible for writing the CLSID.

The IPersistStream::Save method can read from, write to, and seek in the stream; but it must not seek to a location in the stream before that of the seek pointer on entry.

Requirements

Header	objidl.h, objidl.idl
Library	ole32.lib, uuid.lib

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