ILockBytes - File-Based Implementation

Implemented on a byte array object underlying a COM compound file storage object, and designed to read and write directly to a disk file.

When to Use

Methods of ILockBytes are called from the compound file implementations of IStorage and IStream on the compound file storage object created through a call to StgCreateDocfile, so you do not need to call them directly.

Remarks

ILockBytes::ReadAt

This method queries the wrapped pointer for the requested interface.

ILockBytes::WriteAt

This method queries the wrapped pointer for the requested interface.

ILockBytes::Flush

This method queries the wrapped pointer for the requested interface.

ILockBytes::SetSize

This method queries the wrapped pointer for the requested interface.

ILockBytes::LockRegion

The dwLockTypes parameter is set to LOCK_ONLYONCE OR LOCK_EXCLUSIVE, which will allow or restrict access to locked regions.

ILockBytes::UnlockRegion

This method unlocks the region locked by ILockBytes::LockRegion.

ILockBytes::Stat

The COM-provided IStorage::Stat implementation calls the ILockBytes::Stat method to retrieve information about the byte array object. If there is no reasonable name for the byte array, the COM-provided ILockBytes::Stat method returns NULL in the pwcsName field of the STATSTG structure.

See Also

ILockBytes, IStorage, IStream