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Common Device Property Constants

In addition to device information properties, Windows Image Acquisition (WIA) devices have property values stored in the registry that applications read and write. They are associated with the IWiaItem object or IWiaItem2 object. Device properties represent device information such as connection status and device time. Each device property has an associated device property string.

The Device Property Constants listed here are common to most or all WIA hardware devices.

The prefix "WIA_DPA_" indicates a Device Property for All devices and is the naming convention used in C/C++. For scripting purposes these constants use the prefix "Device" and are part of the WiaItemPropertyId enumerated type. The corresponding member name from that script enumeration appears in parentheses next to the C/C++ constant name in the following list.

Constant/value Description
WIA_DPA_CONNECT_STATUS
DeviceConnectStatus
The current connection status for the device. The minidriver creates and maintains this property.
Type: VT_I4, Access: Read-only, Valid values: WIA_PROP_NONE
The property can have the following possible values.
Connect Status Definition
WIA_DEVICE_NOT_CONNECTED Device is not connected.
WIA_DEVICE_CONNECTED Device is connected and operational.

 

WIA_DPA_DEVICE_TIME
DeviceDeviceTime

The current clock time that is stored on the device. The minidriver creates and maintains this property.

Type: VT_UI2 | VT_VECTOR, Access: Read/Write or Read-only, Valid values: WIA_PROP_NONE

This property is supported only by devices that have an internal clock. If the device clock can be set, this property is Read/Write; otherwise, it is Read-only.

WIA devices report time in a SYSTEMTIME structure.

WIA_DPA_FIRMWARE_VERSION
DeviceFirmwareVersion

The device firmware version. This value must be a string value, such as "1.0.4" or "1.0abc". The minidriver creates and maintains this property. If the WIA minidriver does not supply a version resource, the WIA service supplies the value "0.0.0.0" as a default. An application reads this property to determine the version of the WIA minidriver DLL.

Type: VT_BSTR, Access: Read-only, Valid values: WIA_PROP_NONE

Requirements

Requirement Value
Minimum supported client
Windows 2000 Professional, Windows XP [desktop apps only]
Minimum supported server
Windows Server 2003 [desktop apps only]
Header
Wiadef.h