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Re: custom event in IE

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Thomas 'PointedEars' Lahn <PointedEars@web.de> wrote:

> James Kirk wrote:

>> Andrew Poulos <ap_prog@hotmail.com> wrote: 

>>> I used a try/catch and when it fails for IE the "catch" part uses
>>> initCustomEvent

[snip]

>> I have always tried to avoid using try/catch. So just out of my own
>> curiosity, why the try/catch over something liking to the function

[snip]

> If the global object has no CustomEvent property in the MSHTML DOM,
> then such a polyfill would be a possibility. If on the other hand it
> has such a property but the value of it just cannot be called a
> constructor, then the value would be a reference to a host object,
> and it would be unwise to try to overwrite the value.

I would not agree with “unwise”, ill-advised perhaps, I suppose it
really depends on what definition was intended. No argument intended.

I did not intend to infer the usage of the Polyfill example verbatim.

Perhaps something similar to the following:

(function () {

  var CustomEvent = function (event, params) {
    console.log('petaQ');
    params = params || {
      bubbles: false,
      cancelable: false,
      detail: undefined
    };
    var evt = document.createEvent('CustomEvent');
    evt.initCustomEvent(event, 
	                params.bubbles, 
			params.cancelable, 
			params.detail);
    return evt;
  }
  if (typeof (window.CustomEvent) === "function") {
    CustomEvent = window.CustomEvent;
  }
/* 

more script follows

*/

})();

>> or testing in a similar fashion to that function. 

> You cannot determine whether a function can be called as a
> constructor unless you try it.

No know evidence to refute that.

In IE 11 typeof window.CustomEvent === 'object'. I am going to surmise
the same for IE 9 & 10.

[url]http://caniuse.com/#feat=customevent[/url]

Presuming that support for anything older then IE 11 is not being
handled. Is there a reason to redetermine if CustomEvent can be called
as a constructor?

As I previously stated, “curiosity, why the try/catch”, in no way do I
oppose the use of try/catch.


-- 
James Kirk

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Thread

custom event in IE Andrew Poulos <ap_prog@hotmail.com> - 2017-01-10 12:08 +1100
  Re: custom event in IE Andrew Poulos <ap_prog@hotmail.com> - 2017-01-10 12:20 +1100
    Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-10 02:45 +0100
      Re: custom event in IE Andrew Poulos <ap_prog@hotmail.com> - 2017-01-10 15:32 +1100
        Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-10 12:53 +0100
          Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-11 08:25 +0100
        Re: custom event in IE James Kirk <noneya.invalid@gmail.com> - 2017-01-10 21:52 -0500
          Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-11 04:09 +0100
            Re: custom event in IE James Kirk <noneya.invalid@gmail.com> - 2017-01-11 21:31 -0500
              Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-12 14:22 +0100
            Re: custom event in IE Scott Sauyet <scott@sauyet.com> - 2017-01-14 23:01 +0000
              Re: custom event in IE "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-01-15 09:51 -0800
                Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-15 22:37 +0100
                Can we recognize Constructor Functions (was: custom event in IE) Scott Sauyet <scott@sauyet.com> - 2017-01-15 23:39 +0000
                Re: custom event in IE Scott Sauyet <scott@sauyet.com> - 2017-01-15 23:15 +0000
                Re: custom event in IE "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-01-15 22:36 -0800
                Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-16 12:54 +0100
                Re: custom event in IE "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2017-01-16 14:18 -0800
                Re: custom event in IE Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-01-17 00:24 +0100

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