Capture keyboard event CTRL+s

I need to开发者_如何学C fire an event by pressing CTRL+S.

I tried this but it won't work:

if(e.ctrlKey == true && e.keyCode == 81){
        trace("CTRL+S")
    }

How can it be done? Thanks for tips.

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It is keyCode 83 for S (in case if you are making that mistake). Moreover, make sure you add your listener on KEY_UP event. Here is a working sample:

<?xml version="1.0" encoding="utf-8"?>
<s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009" 
                       xmlns:s="library://ns.adobe.com/flex/spark" 
                       xmlns:mx="library://ns.adobe.com/flex/mx">
    <s:layout>
        <s:VerticalLayout/>
    </s:layout>
    <s:Panel title="Panel 3" width="100%" height="200" creationComplete="onCreationComplete()">
        <s:layout>
            <s:VerticalLayout/>
        </s:layout>
        <fx:Script>
            <![CDATA[
            private function onCreationComplete():void{
                this.addEventListener(MouseEvent.CLICK, clickHandler);
                this.addEventListener(KeyboardEvent.KEY_UP,keyPressed);
            }

            private function clickHandler(event:MouseEvent):void {
                stage.focus = this;
            }

            private function keyPressed(evt:KeyboardEvent):void{
                if(evt.ctrlKey && evt.keyCode == 65)
                    trace("CTRL A is pressed");
                if(evt.ctrlKey && evt.keyCode == 66)
                    trace("CTRL B is pressed");
                if(evt.ctrlKey && evt.keyCode == 81)
                    trace("CTRL S is pressed");
            }
            ]]>
        </fx:Script>
    </s:Panel>
</s:WindowedApplication>

---

M.D.'s answer looks very good; it shows how to add event listeners for the keyboard events.

But one thing he didn't mention: if you are running this as a Flash SWF in a browser, the CTRL+S shortcut may be intercepted and consumed by the browser and the Flash Player may never get it. CTRL+S is a pretty common shortcut for saving a page, so don't be surprised if you run into browser focus issues.