| Microsoft DirectX 9.0 |
This topic applies to Windows XP only.
The get_CanStep method queries whether the input source can step frame by frame.
Syntax
HRESULT get_CanStep(
VARIANT_BOOL fBackwards,
VARIANT_BOOL *pfCan
);
Parameters
fBackwards
[in] Use one of the following values.
| Value | Description |
| VARIANT_FALSE | Query whether the input can step forward |
| VARIANT_TRUE | Query whether the input can step backward. |
pfCan
[out] Pointer to a variable that receives one of the following values.
| Value | Description |
| VARIANT_FALSE | The source cannot step in the specified direction. |
| VARIANT_TRUE | The source can step in the specified direction. |
Return Values
The method returns an HRESULT. Possible values include the following.
| Value | Description |
| E_POINTER | NULL pointer argument. |
| ERROR_INVALID_STATE | The graph is not built. Call the Build or View method on the Video Control. |
| S_OK | The method succeeded. |
Note The value ERROR_INVALID_STATE is converted to an HRESULT with the HRESULT_FROM_WIN32 macro.
Remarks
Call the IMSVidCtl::Build or IMSVidCtl::View method before calling this method.
Example Code
VARIANT_BOOL fCan = VARIANT_FALSE;
hr = m_pPlayback->get_CanStep(VARIANT_FALSE, &fCan);
See Also