Control.ProcessKeyPreview(Message) Method
Definition
Important
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Previews a keyboard message.
protected:
virtual bool ProcessKeyPreview(System::Windows::Forms::Message % m);
protected virtual bool ProcessKeyPreview (ref System.Windows.Forms.Message m);
abstract member ProcessKeyPreview : Message -> bool
override this.ProcessKeyPreview : Message -> bool
Protected Overridable Function ProcessKeyPreview (ByRef m As Message) As Boolean
Parameters
Returns
true
if the message was processed by the control; otherwise, false
.
Remarks
This method is called by a child control when the child control receives a keyboard message. The child control calls this method before generating any keyboard events for the message. If this method returns true
, the child control considers the message processed and does not generate any keyboard events. The m
parameter contains the window message to preview. Possible values for the Message.Msg property are WM_CHAR, WM_KEYDOWN, WM_SYSKEYDOWN, WM_KEYUP, and WM_SYSKEYUP. The ProcessKeyPreview method simply sends the character to the parent's ProcessKeyPreview method, or returns false
if the control has no parent. The Form class overrides this method to perform actual processing of dialog keys.
Notes to Inheritors
When overriding the ProcessKeyPreview(Message) method in a derived class, a control should return true
to indicate that it has processed the key. For keys that are not processed by the control, the result of calling the base class's ProcessKeyPreview(Message) method should be returned.
Applies to
See also
.NET