IMoniker::BindToStorage

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Windows Embedded CE 6.0 R3

4/8/2010

This method binds to the object's storage.

Syntax

HRESULT BindToStorage( 
  IBindCtx* pbc, 
  IMoniker* pmkToLeft, 
  REFIID riid, 
  void** ppvObj
);

Parameters

• pbc
  [in] Pointer to the IBindCtx interface on the bind context object to be used during this binding operation. The bind context caches objects bound during the binding process, contains parameters that apply to all operations using the bind context, and provides the means by which the moniker implementation should retrieve information about its environment. For more information, see IBindCtx.

• pmkToLeft
  [in] If the moniker is part of a composite moniker, pointer to the moniker to the left of this moniker. This parameter is primarily used by moniker implementers to enable cooperation between the various components of a composite moniker. Moniker clients should pass NULL.

• riid
  [in] Reference to the identifier of the storage interface requested, whose pointer will be returned in ppvObj. Storage interfaces commonly requested include IStorage, IStream, and ILockBytes.

• ppvObj
  [out] Address of the pointer variable that receives the interface pointer requested in riid. Upon successful return, *ppvObj contains the requested interface pointer to the storage of the object identified by the moniker.

  If ppvObj is non-NULL, the implementation must call the IUnknown::AddRef method on the storage; it is the caller's responsibility to call the IUnknown::Release method.

  If an error occurs, *ppvObj must be set to NULL.

Return Value

The method supports the standard return value E_OUTOFMEMORY. The following table shows the additional return values for this method.

Remarks

There is an important difference between the IMoniker::BindToObject and IMoniker::BindToStorage methods.

If, for example, you have a moniker that identifies a spreadsheet object, calling IMoniker::BindToObject provides access to the spreadsheet object itself, while calling IMoniker::BindToStorage provides access to the storage object in which the spreadsheet resides.

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

Notes to Callers

Although none of the COM moniker classes call this method in their binding operations, it might be appropriate to call it in the implementation of a new moniker class.

You could call this method in an implementation of IMoniker::BindToObject that requires information from the object identified by the pmkToLeft parameter and can get it from the persistent storage of the object without activation.

For example, if your monikers are used to identify objects that can be activated without activating their containers, you may find this method useful.

A client that can read the storage of the object its moniker identifies could also call this method.

Notes to Implementers

Your implementation should locate the persistent storage for the object identified by the current moniker and return the desired interface pointer.

Some types of monikers represent pseudo-objects, which are objects that do not have their own persistent storage. Such objects include some portion of the internal state of its container; as, for example, a range of cells in a spreadsheet.

If your moniker class identifies this type of object, your implementation of IMoniker::BindToStorage should return the error MK_E_NOSTORAGE.

If the bind context's BIND_OPTS structure specifies the BINDFLAGS_JUSTTESTEXISTENCE flag, your implementation has the option of returning NULL in ppvObj (although it can also ignore the flag and perform the complete binding operation).

Requirements

See Also

Reference

IStorage
IStream
ILockBytes
IMoniker::BindToObject
IUnknown::AddRef
IUnknown::Release
BIND_OPTS