IStillImageW::CreateDevice method (sti.h)
The IStillImage::CreateDevice method creates an instance of the COM object that defines the IStiDevice COM Interface, and returns a pointer to the interface.
Syntax
HRESULT CreateDevice(
[in] LPWSTR pwszDeviceName,
DWORD dwMode,
[out] PSTIDEVICE *pDevice,
[in, optional] LPUNKNOWN punkOuter
);
Parameters
[in] pwszDeviceName
Caller-supplied pointer to a string representing an internal device name, obtained by calling IStillImage::GetSTILaunchInformation or IStillImage::GetDeviceList.
dwMode
Caller-supplied constant value indicating the Transfer Modes in which the device is to be used. The following values are valid.
| Mode | Description |
|---|---|
| STI_DEVICE_CREATE_BOTH | The device is being opened for both obtaining status and transferring data. |
| STI_DEVICE_CREATE_DATA | The device is being opened only for data transfers. |
| STI_DEVICE_CREATE_STATUS | The device is being opened only for obtaining status information. |
[out] pDevice
Receives a pointer to the IStiDevice COM Interface.
[in, optional] punkOuter
Optional, caller-supplied pointer to the "controlling unknown" for object aggregation. See the following Remarks section.
Return value
If the operation succeeds, the method returns S_OK. Otherwise, it returns one of the STIERR-prefixed error codes defined in stierr.h.
Remarks
For an application to use the IStiDevice interface, it must first call IStillImage::StiCreateInstance to get a pointer to the IStillImage interface, then call IStillImage::CreateDevice to get a pointer to the IStiDevice interface. The pointer received in pDevice is used subsequently when calling IStiDevice methods, as illustrated in the sample still image code, to obtain access to the specified device.
If you want to create an aggregate COM object that includes IStiDevice, you must supply a pointer to the "controlling unknown" in punkOuter. In most cases you will not be creating an aggregate object, so punkOuter should be NULL. Object aggregation and the controlling unknown are described in the Microsoft Windows SDK documentation and in the Component Object Model Specification.
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Desktop |
| Header | sti.h (include Sti.h) |