Empty chart created on Update Panel refresh

Question

Hello everybody,

I have a problem  with a chart control within an ajax update panel.

On my page there is an update panel which contains a chart control and a link button which is use for triggering the actual values. So at the link button click event i call the databind method to get the new values for the chart, that works all great.
But sometimes (at first call of the page) the update panel gets refreshed a second time (without trigger) and a new image without values is generated.

I figured out that at every update panel refresh a new chart image is rendered. I can see that if i take a look in the temporary char image folder.
 There exists the possibility to enable view state, but my chart contains a very high number of values an that will cost too much traffic. I also don't want to render a chart at every update panel load event., because i have a timer which calls another update panel cyclic an so the update panel load event for the chart control is also called cyclic at server.

Is there a workaround that a new "image" is only created e.g. on a click event and not when the site gets refreshed?

My Settingts:

Imagelocation: ~/ChartImages/ChartPic_#SEQ(100,10000)
ImageStoreMode: UseImageLocation

Answer 1

try rebinding the chart again.

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SSN "If you want to live a happy life, tie it to a goal. Not to people or things." : Albert Einstein

Answer 2

yes i know that will work, but my site implements a cyclic timer which refreshs every 5 seconds another control. so also my chart will be refreshed and the server must render every 5 seconds a new chart.

Answer 3

did you try EnableViewState = true for chat

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SSN "If you want to live a happy life, tie it to a goal. Not to people or things." : Albert Einstein

Answer 4

did you try EnableViewState = true for chat

I think this is what the OP is asking. Using this will ensure that the chart doesn't get refreshed unless you do it in code.

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Answer 5

yes i tried to set EnableViewState to true, but my chart may have about 10000 values an so that would cost to much traffic!

Answer 6

You really only have two options... Persist the data in the view state or keep the state on the server by rebinding the chart every time.

Alex.

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http://blogs.msdn.com/alexgor