Path: csiph.com!aioe.org!.POSTED!not-for-mail
From: Joao Rodrigues <jr@none.com>
Newsgroups: comp.lang.javascript
Subject: Re: Interrogation of Shift-Key state
Date: Sat, 25 Jun 2016 20:34:47 -0300
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On 06/25/2016 09:59 AM, Janis Papanagnou wrote:
> I want to interrogate the boolean state of the Shift-Key (pressed or not).
>
> I learned it is possible to define event-handlers to control keyup/keydown
> events,

Yes, it is, but the onkeyup event cannot be cancelled just in case you 
need to.

> then I could adjust some global variable that I can interrogate
> where I need that information. But that is bulky and seems unnecessary(?)
> complex.

A global variable is not a good idea. And you may capture the shift Key 
pressing whenever needed.

>
> My application context is a function that is triggered when a button is
> pressed. Is there a simple way to just interrogate the Shift-Key status
> in that function?

Just a simple example using the onkeydown event to prevent Shift key:

// HTML
<label for="txt1">TextBox1</label>
<input id="txt1" onkeydown="return getKey(event);" type="text" />

<script type="text/javascript">
function getKey(e) {
   if (!e) e = window.event;
   if (e.shiftKey) {
     alert('shiftKey is not allowed.');
     return false;
   }
   return true;
}
</script>

-- 
Joao Rodrigues