The framework calls this member function to notify an application or device driver of a change to the hardware configuration of a device or the computer.
afx_msg BOOL OnDeviceChange( UINT nEventType, DWORD_PTR dwData );
- An event type. See the Remarks section for a description of the available values
- The address of a structure that contains event-specific data. Its meaning depends on the given event.
For devices that offer software-controllable features, such as ejection and locking, the operating system typically sends a DBT_DEVICEREMOVEPENDING message to let applications and device drivers end their use of the device gracefully.
If the operating system forcefully removes of a device, it may not send a DBT_DEVICEQUERYREMOVE message before doing so.
The nEvent parameter can be one of these values:
- DBT_DEVICEARRIVAL A device has been inserted and is now available.
- DBT_DEVICEQUERYREMOVE Permission to remove a device is requested. Any application can deny this request and cancel the removal.
- DBT_DEVICEQUERYREMOVEFAILED Request to remove a device has been canceled.
- DBT_DEVICEREMOVEPENDING Device is about to be removed. Cannot be denied.
- DBT_DEVICEREMOVECOMPLETE Device has been removed.
- DBT_DEVICETYPESPECIFIC Device-specific event.
- DBT_CONFIGCHANGED Current configuration has changed.
- DBT_DEVNODES_CHANGED Device node has changed.
Note This member function is called by the framework to allow your application to handle a Windows message. The parameters passed to your function reflect the parameters received by the framework when the message was received. If you call the base-class implementation of this function, that implementation will use the parameters originally passed with the message and not the parameters you supply to the function.