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Javascript Image refresh


Question

Hi,

Ive been trying to make this webpage which refreshes one single image from the server every 'x' seconds. I have no knowledge of javascript so I used google to find something to suit my needs. The script I obtained works fine apart from the fact that sometimes it displays a blank image. (This happens more on my mobile device (Windows mobile IE) than laptop, most probably due to bandwidth issues.

Is there a way in JS to only display the image once the browser knows that the image has been completely downloaded and if it has not been completely downloaded, keep the last image displayed. Any help will be appreciated. Thank you.

Edited by .AlleymaN
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https://www.neowin.net/forum/topic/513381-javascript-image-refresh/
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10 answers to this question

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java script:

function reloadIt()
  {
  if (document.getElementById("it"))
	{
	document.getElementById("it").src = document.getElementById("it").src;
	setTimeout("reloadIt()", 5000);
	}
   else
	{
	setTimeout("reloadIt()", 5000);
	}
  }

window.onload = reloadIt();

Just change 5000 to the delay in milliseconds you want - 10000 would be 10 seconds delay.

HTML Image code:

<img src="something.jpg" id="it" alt="Image" />

And change the "something.jpg" to the source of the image.

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Tried the script above, didnt work. For some reason it didnt even refresh the image. Tried placing the script both within the < head > and < body > tags with no luck. Is there anything else I should try?

Edit: IE gives me error on the same line as the window.onload function with the error "Not implemented". Tried Opera too, no luck.

Edited by .AlleymaN
  • 0

Mmkay, ditch the last line of the Javascript, and amend the image code to

&lt;img src="something.jpg" id="it" alt="Image" onload="reloadIt();" /&gt;

Should work I think :s

BTW, for JS debugging, FF is by FAR the most useful. I use Opera as my browser of choice, but FF is much better for JS debugging IMO.

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&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">;html xmlns="http://www.w3.org/1999/xhtml">;head&gt;
&lt;script type="text/javascript"&gt;
refreshImage = function()
{
img = document.getElementById("cam");
img.src="https://ephratareview.com/cam/mainstate.jpg?randMath.random();
}
&lt;/script&gt;
&lt;meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /&gt;
&lt;title&gt;Auto-Refresh&lt;/title&gt;
&lt;/head&gt;
&lt;body onload="window.setInterval(refreshImage, 1*1000);"&gt;
&lt;img src="https://ephratareview.com/cam/mainstate.jpg" id="cam" /&gt;
&lt;/body&gt;
&lt;/html&gt;

I just copy and pasted this from an answer I gave in an other thread. Hasn't been tested in IE7, but should be fine.

  • 0
  On 19/11/2006 at 02:25, Ahmadinejad said:

&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">;html xmlns="http://www.w3.org/1999/xhtml">;head&gt;
&lt;script type="text/javascript"&gt;
refreshImage = function()
{
img = document.getElementById("cam");
img.src="https://ephratareview.com/cam/mainstate.jpg?randMath.random();
}
&lt;/script&gt;
&lt;meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /&gt;
&lt;title&gt;Auto-Refresh&lt;/title&gt;
&lt;/head&gt;
&lt;body onload="window.setInterval(refreshImage, 1*1000);"&gt;
&lt;img src="https://ephratareview.com/cam/mainstate.jpg" id="cam" /&gt;
&lt;/body&gt;
&lt;/html&gt;

I just copy and pasted this from an answer I gave in an other thread. Hasn't been tested in IE7, but should be fine.

This topic might be old but i just wanted to say thanks to Ahmadinejad for the code he provided i used it on a recent project and it worked as advertised.

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