CA_ServerGetIfaceFromObjHandle
HRESULT CA_ServerGetIfaceFromObjHandle (CAServerObjHandle serverObjectHandle, const IID *interfaceId, void *interfacePtr);
Purpose
Gets an interface pointer from the object whose handle is passed in the first parameter.
Typically this function is used to obtain interface pointers that are returned to ActiveX Clients requesting them.
Parameters
| Input | ||
| Name | Type | Description |
| serverObjectHandle | CAServerObjHandle | The handle to an ActiveX object in your ActiveX server. |
| interfaceId | const IID * | The interface id of the interface requested from the object. |
| Output | ||
| Name | Type | Description |
| interfacePtr | void * | The interface pointer (of the type passed in the interfaceId parameter) obtained from your ActiveX object. If your ActiveX object does not implement this type of interface, then this parameter is set to NULL. Pass the address of an interface pointer variable of the required interface type. Typically this interface pointer is returned to ActiveX clients requesting them. If these interface pointers need to be disposed (and not returned to the ActiveX clients), call the Release method on the interface pointer as follows: IFoo *pIFoo = NULL; pIFoo->lpVtbl->Release (pIFoo); pIFoo = NULL; } |
Return Value
| Name | Type | Description | ||
| status | HRESULT | A value indicating whether an error occurred. Function failure is indicated by a negative error code. Error codes are defined in CVIversion\include\cviauto.h and <Program Files>\National Instruments\Shared\MSDTRedistributables\SDKHeaderFiles\8.1\winerror.h. The LabWindows/CVI ActiveX Library explicitly returns error codes. Other error codes in winerror.h are generated by the COM runtime and passed on to you by the ActiveX Library. You can use CA_GetAutomationErrorString to get the description of an error code or CA_DisplayErrorInfo to display the description of the error code.
The error codes defined in <Program Files>\National Instruments\Shared\MSDTRedistributables\SDKHeaderFiles\8.1\winerror.h are too numerous to display here. These error codes can be returned to your ActiveX clients. |
Additional Information
Library: ActiveX Library
Include file: cviauto.h
LabWindows/CVI compatibility: LabWindows/CVI 6.0 and later