c# - In a Control extension, Override or addHandler? -



c# - In a Control extension, Override or addHandler? -

i created extension datagrid. know improve way thing in event.

is improve add together handler :

class mydatagrid : datagrid { public mydatagrid() { this.previewkeydown+= mydatagrid_previewkeydown; } protected void mydatagrid_previewkeydown(/* args */) {/* stuff */} }

or override this:

class mydatagrid : datagrid { public mydatagrid() { } protected override void onpreviewkeydown(/* args */) {/* stuff */} }

and if allow base.onpreviewkeydown(e); in override, same eventhandler?

it not matter either way. said, should override method -- whole purpose handle event within control. if add together event handler, needlessly adding method event's invocation list (ie, slight performance hit).

if want strict/fanatical performance, create "mydatagrid" class "sealed".

sealed class mydatagrid : datagrid { ... }

that allows compiler/runtime determine doesn't need check overrides of virtual method "onpreviewkeydown" above "mydatagrid" class.

c# wpf

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