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Re: Which type of network access for this situation?

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Stefan Weiss wrote:

> bit-naughty@hotmail.com wrote:
>> Suppose after a page is loaded, I want to download some stuff (text or
>> HTML) later, or even immediately and display it. But NOT on a button
>> click, more like say, after a timer goes off or something. What type of
>> networking shit do I use for this? Does it call for AJAX, WebSockets or
>> the DataChannel part of the WebRTC API, which I just got to know about?
>> I'm still not really clear about what the exact differences between each
>> of them are....
> 
> Use the XMLHttpRequest object. […]

Not necessarily.  If a resource is to be downloaded to be saved as a file in 
the filesystem in a user-specified location after a “timer goes off”, then a 
simple

  var timer = window.setTimeout(function () {
    window.clearTimeout(timer);

    window.location = "…";
  }, 42);

suffices, where 42 is the number of milliseconds after this call that the 
“timer goes off” (in backwards-compatible code, it should not be less than 
10).  The resource needs to be served with the proper MIME media type; if it 
should be downloaded to be saved as a file, then “application/octet-stream” 
will trigger the browser’s download dialog.

Any suitable set of statements can be used instead of the assignment to 
“window.location”.  For example, if an image resource is to be displayed, 
code to set the “src” property of an “img” element object, optionally create 
the latter and insert the corresponding “img” node into the document tree 
first, can be used.

If one uses window.setTimeout(), one should also handle the case of 
navigating away before the “timer goes off”, so as not to potentially 
execute code that potentielly produces errors because of missing objects:

  window.onunload = function () {
    window.clearTimeout(timer);
  };

It may be useful to establish a timeout registry that clears all registered 
timeouts in that case.

The usual caveats regarding the use of host-provided features apply.

-- 
PointedEars
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Which type of network access for this situation? bit-naughty@hotmail.com - 2017-04-17 11:53 -0700
  Re: Which type of network access for this situation? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-18 00:57 +0100
  Re: Which type of network access for this situation? Stefan Weiss <krewecherl@gmail.com> - 2017-04-18 01:57 +0200
    Re: Which type of network access for this situation? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-18 02:52 +0200
      Re: Which type of network access for this situation? Stefan Weiss <krewecherl@gmail.com> - 2017-04-18 03:13 +0200
        Re: Which type of network access for this situation? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-04-18 05:40 +0200
        Re: Which type of network access for this situation? bit-naughty@hotmail.com - 2017-04-18 08:22 -0700
          Re: Which type of network access for this situation? bit-naughty@hotmail.com - 2017-04-18 08:28 -0700
          Re: Which type of network access for this situation? Jon Ribbens <jon+usenet@unequivocal.eu> - 2017-04-18 16:08 +0000
            Re: Which type of network access for this situation? bit-naughty@hotmail.com - 2017-04-19 23:44 -0700
              Re: Which type of network access for this situation? Jon Ribbens <jon+usenet@unequivocal.eu> - 2017-04-20 10:15 +0000
                Re: Which type of network access for this situation? "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2017-04-20 12:56 +0200
  Re: Which type of network access for this situation? maherrj@googlemail.com - 2017-04-17 17:23 -0700
  Re: Which type of network access for this situation? Stefan Weiss <krewecherl@gmail.com> - 2017-04-18 03:29 +0200

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