IsInputKey Method
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Control.IsInputKey Method (Keys)


Determines whether the specified key is a regular input key or a special key that requires preprocessing.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

[<UIPermissionAttribute(SecurityAction.InheritanceDemand, Window = UIPermissionWindow.AllWindows)>]
abstract IsInputKey : 
        keyData:Keys -> bool
[<UIPermissionAttribute(SecurityAction.InheritanceDemand, Window = UIPermissionWindow.AllWindows)>]
override IsInputKey : 
        keyData:Keys -> bool


Type: System.Windows.Forms.Keys

One of the Keys values.

Return Value

Type: System.Boolean

true if the specified key is a regular input key; otherwise, false.

Call the IsInputKey method to determine whether the key specified by the keyData parameter is an input key that the control wants. This method is called during window message preprocessing to determine whether the specified input key should be preprocessed or sent directly to the control. If IsInputKey returns true, the specified key is sent directly to the control. If IsInputKey returns false, the specified key is preprocessed and only sent to the control if it is not consumed by the preprocessing phase. Keys that are preprocessed include the TAB, RETURN, ESC, and the UP ARROW, DOWN ARROW, LEFT ARROW, and RIGHT ARROW keys.

Legacy Code Example

The following code example shows you how to override the IsInputKey method for a TextBox control. In this example, the TabTextBox class handles the TAB key. When the TabTextBox has the focus and the user presses the TAB key four spaces are added at the text insertion point, replacing any selected text. By default, the TextBox control handles the TAB key by moving the input focus to the next control. In this case, the keypress never reaches the OnKeyDown method override. To prevent this default behavior, the IsInputKey method override returns true when the user presses the TAB key. For all other keypresses, the IsInputKey method override returns the result of calling the base-class version of the method.

No code example is currently available or this language may not be supported.

for all windows for inheriting classes to call this method. Associated enumeration: AllWindows value of UIPermissionWindow.

.NET Framework
Available since 1.1
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