DEV_QUERY_RESULT_ACTION_DATA structure (devquerydef.h)

Provides information to the PDEV_QUERY_RESULT_CALLBACK callback function.

Syntax

typedef struct _DEV_QUERY_RESULT_ACTION_DATA {
  DEV_QUERY_RESULT_ACTION          Action;
  union _DEV_QUERY_RESULT_UPDATE_PAYLOAD {
    DEV_QUERY_STATE State;
    DEV_OBJECT      DeviceObject;
  } Data;
} DEV_QUERY_RESULT_ACTION_DATA, *PDEV_QUERY_RESULT_ACTION_DATA;

Members

Action

A value from the DEV_QUERY_RESULT_ACTION enumeration specifying the type of action being performed.

Data

A value from the _DEV_QUERY_RESULT_UPDATE_PAYLOAD union.

Data.State

A value from the DEV_QUERY_STATE enumeration specifying the current state of the query. This member is valid only if Action is equal to DevQueryResultStateChange.

Data.DeviceObject

A DEV_OBJECT structure associated with the query result. This member is only valid if Action is equal to DevQueryResultAdd, DevQueryResultUpdate, or DevQueryResultRemove. The following table specifies how the DevObject field should be interpreted, depending on the value of the Action field.

Action value	Interpretation of DeviceObject
DevQueryResultAdd	DeviceObject represents a new object being added to the query’s result set due to it meeting the criteria of the query’s filter parameters. DeviceObject will contain a list of properties for all properties requested by the query.
DevQueryResultUpdate	DeviceObject represents an object already in the query’s result set that has had a requested property changed. The property list in DeviceObject will provide the properties that have changed.
DevQueryResultRemove	DeviceObject represents an object that is being removed from the query’s result set due to it no longer meeting the criteria of the query’s filter parameters.

_DEV_QUERY_RESULT_UPDATE_PAYLOAD

The union containing the the state or object associated with the action.

Requirements

Requirement	Value
Header	devquerydef.h