The KeyDown Event is available in LEADTOOLS Document and Medical Imaging toolkits.
An event that triggers when a key is pressed when your control has focus.
Syntax
| Visual Basic (Declaration) | |
|---|---|
Event KeyDown As KeyEventHandler | |
| Visual Basic (Usage) |  Copy Code |
|---|---|
Dim instance As IAnnAutomationControl Dim handler As KeyEventHandler AddHandler instance.KeyDown, handler | |
| C# | |
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event KeyEventHandler KeyDown | |
| C++/CLI | |
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event KeyEventHandler^ KeyDown | |
Event Data
The event handler receives an argument of type KeyEventArgs containing data related to this event. The following KeyEventArgs properties provide information specific to this event.
| Property | Description |
|---|---|
| Alt | Gets a value indicating whether the ALT key was pressed. |
| Control | Gets a value indicating whether the CTRL key was pressed. |
| Handled | Gets or sets a value indicating whether the event was handled. |
| KeyCode | Gets the keyboard code for a System.Windows.Forms.Control.KeyDown or System.Windows.Forms.Control.KeyUp event. |
| KeyData | Gets the key data for a System.Windows.Forms.Control.KeyDown or System.Windows.Forms.Control.KeyUp event. |
| KeyValue | Gets the keyboard value for a System.Windows.Forms.Control.KeyDown or System.Windows.Forms.Control.KeyUp event. |
| Modifiers | Gets the modifier flags for a System.Windows.Forms.Control.KeyDown or System.Windows.Forms.Control.KeyUp event. The flags indicate which combination of CTRL, SHIFT, and ALT keys was pressed. |
| Shift | Gets a value indicating whether the SHIFT key was pressed. |
| SuppressKeyPress | Gets or sets a value indicating whether the key event should be passed on to the underlying control. |
Example
For an example, refer to IAnnAutomationControl.
Remarks
If your control is derived from the standard System.Windows.Forms.Control, then you do not need to implement this event (since the default System.Windows.Forms.Control.KeyDown will be used).
Requirements
Target Platforms: Microsoft .NET Framework 2.0, Windows 2000, Windows XP, Windows Server 2003 family, Windows Server 2008 family, Windows Vista, Windows 7