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Event for Control.

Generated on a control that has keyboard focus. If a key press matches a keyboard shortcut in the VI menu, such as Ctrl-C or Ctrl-V, LabVIEW does not generate a Key Down event, regardless of whether the menu item is enabled. The Key Down? event is a filter event.

For a filter event, if you do not wire an element in the Event Filter Node that appears on the right-hand side of the event case, the default value of the element is the value output by the corresponding element in the Event Data Node on the left-hand side of the event case.

Note  LabVIEW only generates events for the Cluster»All Elements source when the cluster has keyboard focus, not when an individual element inside the cluster has keyboard focus.

Event Data Fields

Name	Description
Source	Source of the event. 0 LabVIEW UI 1 ActiveX 2 .NET 25 User Event n Other
Type	Type of event that occurred, such as Mouse Down, Value Change, Timeout, and so on.
Time	Value of the millisecond timer when the event occurred.
CtlRef	Reference to the control on which the event occurred.
Char	ASCII value that corresponds to the key pressed on the keyboard, or zero if the character is not an ASCII character. You also can modify the data returned by this event data field.
VKey	Enumerated type indicating the virtual key code of the key pressed. Values include ASCII, Shift, NumLock, F1, and so on. You also can modify the data received from this event data field. Note  VKey has separate values for the <Enter> key on the alphanumeric keyboard and <Enter> key on the numeric keypad.
ScanCode	Scan code unique for each key on the keyboard. The values are unique for each physical key, and allow you to match Key Up and Key Down events.
Mods	Cluster of Booleans that contain platform-independent modifiers. LabVIEW returns all platform-dependent modifiers in the PlatMods event data field. For key events, this event returns a Boolean indicating if the event occurred on the numeric keypad. For mouse events, this event returns a Boolean indicating if the event was a double-click. For both events, a Boolean is returned if the platform-independent menu key, such as <Ctrl> on Windows or <Command> on Mac OS, was pressed when the event occurred. For filter events, you can modify the data returned by this event data field.
PlatMods	Cluster of Booleans that contain platform-dependent modifiers. Specifies if platform-dependent keys, such as <Ctrl>, <Shift>, <Alt>, <Command>, and <Option> were held down when the event was triggered. For filter events, you can modify the data returned by this event data field. A key can be both a Mod and PlatMod. For example, <Ctrl> is the platform-independent menu key on Windows, but you also can use it in platform-dependent programming.
FocusObj	A reference to the object that has keyboard focus. When the event is for a control, it might be a sub-component, like a scale, label, and so on, rather than the control itself. You also can modify the data returned by this event data field. You cannot generate any Key events on a control inside a cluster.
Discard?	Allows you to prevent LabVIEW from processing the event, bypassing the behavior normally triggered by that event. The default is FALSE.