IExpressEntity::SearchParentInterface

This method attempts to return an pointer to the interface specified by looking through all the parent relationships accessible from this entity. It is most often used when a Design pointer is needed and the only interface available is, for example, a Port pointer.

Syntax

C++
HRESULT SearchParentInterface( REFIID riid, IDispatch *SearchParentInterface );

Parameters

Return value

This method returns S_OK if the enumerator object is successfully instantiated or there are no connections. Other possible values include the following.

Return code	Description
E_OUTOFMEMORY	Insufficient memory is available for the operation.
OLE_E_ADVISENOTSUPPORTED	Advisory notifications are not supported by this object.

Remarks

This method is useful for searching all parent interfaces. It essentially walks successively through immediate parents using the IExpressEntity::Parent property until it finds the interface specified. In most cases, this behavior is desirable. If it is desirable to find out only if the immediate parent supports a given interface, the IExpressEntity::Parent property should be used instead.

Example Code

The following example uses smart pointers assuming that a port interface is known.

#import "express.tlb"

MyFunction(eXpress::IPortPtr iPort)

{

using namespace eXpress;

IDesignPtr iDesign;

IExpressEntityPtr iEntity;

try

{

iEntity = iPort;

iDesign = iEntity->SearchParentInterface(__uuidof(IDesign));

}

catch (_com_error&) {}

// Now we can use iDesign to search for other things...