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Re: Multiple inputs with same event

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Andrew Poulos wrote:

> On 9/06/2020 10:49 am, Thomas 'PointedEars' Lahn wrote:
>> It is actually not necessary (but recommended by some people) do this
>> with assignment with scripting.  However, a form element can have an
>> “onchange” event-handler attribute that can execute code, like a
>> function:
>> 
>>    <form … onchange='my.change(this, event)'>
>>      …
>>    </form>
>> 
>> Then the form element does not need an “id” attribute, and the reference
>> to object representing the current propagated event and to the object
>> representing the form element, can be obtained by passing the “event” and
>> “this” values respectively.
>> 
>> Note that the “change” event might not be fired for every control.
> 
> For the few times that an input is changed with code, and so doesn't
> trigger an "on change" event, I'm going to trigger the change with
> 
> document.querySelector('form').dispatchEvent(new Event('change'));

  document.forms[0].dispatchEvent(new Event('change'));
  ^^^^^^^^^^^^^^^^^
suffices as for the first reference, and is more efficient and compatible. 

Your “change” event might need an event target to be useful; then just 
passing the constructor return value might not be sufficient.

Note that for compatibility you may need an “Event” wrapper, like the 
following quickhack:
 
  var _isHostMethod = jsx.object.isHostMethod; // [1]
  var e = null;

  if (typeof Event == 'function')
  {
    try
    {
      e = new Event('change');
    }
    catch (e)
    {
      if (!(e instanceof TypeError)) throw e;
    }
  } 

  if ((!e || e.type != 'change') && _isHostMethod(document, 'createEvent'))
  {
    try
    {
      e = document.createEvent('Event');
      if (_isHostMethod(e, 'initEvent')) e.initEvent('change', true, true);
    }
    catch (e)
    {
      if (_isHostMethod(_global, 'console', 'log')) console.log(e);
    }
  }

<https://developer.mozilla.org/en-US/docs/Web/Guide/Events/Creating_and_triggering_events>

[1] <https://github.com/PointedEars/JSX/blob/master/object.js#L1051>

(Maybe I find the time to write a general wrapper during the summer 
holidays, and update JSX.)
 
> Is it appropriate as the value of "this" won't change?

In theory, yes.  It depends on what you want to do.

-- 
PointedEars
FAQ: <http://PointedEars.de/faq> | <http://PointedEars.de/es-matrix>
<https://github.com/PointedEars> | <http://PointedEars.de/wsvn/>
Twitter: @PointedEars2 | Please do not cc me./Bitte keine Kopien per E-Mail.

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Thread

Multiple inputs with same event Andrew Poulos <ap_prog@hotmail.com> - 2020-06-07 10:36 +1000
  Re: Multiple inputs with same event Arno Welzel <usenet@arnowelzel.de> - 2020-06-07 11:06 +0200
    Re: Multiple inputs with same event "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2020-06-07 13:09 +0200
      Re: Multiple inputs with same event Luuk <luuk@invalid.lan> - 2020-06-07 15:40 +0200
        Re: Multiple inputs with same event "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2020-06-08 00:37 +0200
          Re: Multiple inputs with same event Julio Di Egidio <julio@diegidio.name> - 2020-06-08 07:44 -0700
  Re: Multiple inputs with same event James Kirk <noneya.invalid@gmail.com> - 2020-06-07 10:30 -0400
  Re: Multiple inputs with same event JJ <jj4public@vfemail.net> - 2020-06-07 23:49 +0700
  Re: Multiple inputs with same event "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2020-06-07 12:56 -0700
    Re: Multiple inputs with same event Andrew Poulos <ap_prog@hotmail.com> - 2020-06-08 11:39 +1000
      Re: Multiple inputs with same event Gregor Kofler <usenet@gregorkofler.com> - 2020-06-08 11:33 +0200
    Re: Multiple inputs with same event Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2020-06-09 02:49 +0200
      Re: Multiple inputs with same event Andrew Poulos <ap_prog@hotmail.com> - 2020-06-10 17:19 +1000
        Re: Multiple inputs with same event Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2020-06-10 17:12 +0200
          Re: Multiple inputs with same event Andrew Poulos <ap_prog@hotmail.com> - 2020-06-11 15:43 +1000

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