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james hendersonFlag for United States of America

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javascript timer "locks up" the web page

i have a dll that raises events.  i have a javascript function event handler.  this works well, as long as I call a function in the dll to return the event.  but there are events that happen outside the browser that I need to respond to.  I created a javascript timer to fetch the events, but that won't let the page respond to button clicks, text box entry, etc.

how can i implement this so that the page stays responsive?  i am using straight javascript and html, the dll is loaded on the page as an embedded object.
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Julian Hansen
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How are you fetching events outside the browser?
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the dll has a function called "FetchEvents()".  so the object is:
 <object classid="clsid:55527FAD-5E60-4F44-867B-9F6E7B0DB9DD" id="ica">
        </object>

and the call is form1.ica.FetchEvents();
Are you doing something like this

setInterval('fetchEvents()', 1000);

function fetcEvents()
{
   // Make your call to the object here.
}

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And you are saying that is causing the page to not be responsive? Why is that? Does the fetchEvents method take a long time to complete?
How often are you calling it?
here's the cycle:
1.  page loads and it logs into the object ( form1.ica.init() ) through javascript. (ica is a com dll).
2.  there is a javascript event handler at the top of the page, an when init() is called on ica, ica raises an event that is captured by the event handler.
3.  if I call another method on the object, like form1.ica.changestate(), i follow that with a call to form1.ica.FetchEvents(), which forces the event to be raised.

i want to put the FetchEvents() method on a javascript timer, but when I do the rest of the page becomes unresponsive.
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Julian Hansen
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I increased the timeout to 60000 (60 seconds) but that didn't help.
It would help if there was a link or some code to look at - can you post your javascript implementation
thanks for your help, Julian, but I found a different solution.  I created an async version of the method I'm calling and it works like a champ.  I appreciate the time and the help.
Well that would do it - refer my comment earlier

How long does it take for the call to the DLL to complete (in FetchEvents)

Glad you got sorted though - thanks for the points and good luck with your project.