SetupDiGetClassPropertyW function (setupapi.h)

Article
10/13/2021

The SetupDiGetClassProperty function retrieves a device property that is set for a device setup class or a device interface class.

Syntax

WINSETUPAPI BOOL SetupDiGetClassPropertyW(
  [in]            const GUID       *ClassGuid,
  [in]            const DEVPROPKEY *PropertyKey,
  [out]           DEVPROPTYPE      *PropertyType,
  [out]           PBYTE            PropertyBuffer,
  [in]            DWORD            PropertyBufferSize,
  [out, optional] PDWORD           RequiredSize,
  [in]            DWORD            Flags
);

Parameters

[in] ClassGuid

A pointer to a GUID that identifies the device setup class or device interface class for which to retrieve a device property that is set for the device class. For information about specifying the class type, see the Flags parameter.

[in] PropertyKey

A pointer to a DEVPROPKEY structure that represents the device property key of the requested device class property.

[out] PropertyType

A pointer to a DEVPROPTYPE-typed variable that receives the property-data-type identifier of the requested device class property, where the property-data-type identifier is the bitwise OR between a base-data-type identifier and, if the base data type is modified, a property-data-type modifier.

[out] PropertyBuffer

A pointer to a buffer that receives the requested device class property. SetupDiGetClassProperty retrieves the requested property value only if the buffer is large enough to hold all the property value data. The pointer can be NULL. If the pointer is set to NULL and RequiredSize is supplied, SetupDiGetClassProperty returns the size of the device class property, in bytes, in *RequiredSize.

[in] PropertyBufferSize

The size, in bytes, of the PropertyBuffer buffer. If PropertyBuffer is set to NULL, PropertyBufferSize must be set to zero.

[out, optional] RequiredSize

A pointer to a DWORD-typed variable that receives either the size, in bytes, of the device class property if the device class property is retrieved or the required buffer size if the buffer is not large enough. This pointer can be set to NULL.

[in] Flags

One of the following values, which specifies whether the class is a device setup class or a device interface class.

DICLASSPROP_INSTALLER

ClassGuid specifies a device setup class. This flag cannot be used with DICLASSPROP_INTERFACE.

DICLASSPROP_INTERFACE

ClassGuid specifies a device interface class. This flag cannot be used with DICLASSPROP_INSTALLER.

Return value

SetupDiGetClassProperty returns TRUE if it is successful. Otherwise, it returns FALSE, and the logged error can be retrieved by calling GetLastError.

The following table includes some of the more common error codes that this function might log.

Return code	Description
ERROR_INVALID_FLAGS	The value of Flags is not zero.
ERROR_INVALID_CLASS	The device setup class that is specified by ClassGuid is not valid. This error can occur only if the DICLASSPROP_INSTALLER flag is specified.
ERROR_INVALID_PARAMETER	An unspecified parameter is not valid.
ERROR_INVALID_REG_PROPERTY	The property key that is supplied by PropertyKey is not valid.
ERROR_INVALID_REFERENCE_STRING	The device interface reference string is not valid. This error can be returned if the DICLASSPROP_INTERFACE flag is specified.
ERROR_INVALID_DATA	An unspecified internal data value was not valid.
ERROR_INVALID_USER_BUFFER	A user buffer is not valid. One possibility is that PropertyBuffer is NULL, and PropertyBufferSize is not zero.
ERROR_NO_SUCH_INTERFACE_CLASS	The device interface class that is specified by ClassGuid does not exist. This error can occur only if the DICLASSPROP_INTERFACE flag is specified.
ERROR_INSUFFICIENT_BUFFER	An internal data buffer that was passed to a system call was too small.
ERROR_NOT_ENOUGH_MEMORY	There was not enough system memory available to complete the operation.
ERROR_NOT_FOUND	The requested device property does not exist.
ERROR_ACCESS_DENIED	The caller does not have Administrator privileges.

Remarks

SetupDiGetClassProperty is part of the unified device property model.

SetupAPI supports only a Unicode version of SetupDiGetClassProperty.

A caller of SetupDiGetClassProperty must be a member of the Administrators group to set a device interface property.

To obtain the device property keys that represent the device properties that are set for a device class on a local computer, call SetupDiGetClassPropertyKeys.

To retrieve a device class property on a remote computer, call SetupDiGetClassPropertyEx.

To set a device class property on a local computer, call SetupDiSetClassProperty, and to set a device class property on a remote computer, call SetupDiSetClassPropertyEx.

Requirements

Requirement	Value
Minimum supported client	Available in Windows Vista and later versions of Windows.
Target Platform	DesktopFor universal, call CM_Get_Class_Property
Header	setupapi.h (include Setupapi.h)
Library	Setupapi.lib