Understanding Drawing and Download As Image

[cjherasmus]

Hi,

I'm trying to understand why my chart is downloaded empty if I put the "drawing" code in a button event vs. putting it in the page load event. See attached example.

If the chart code is in the page-load event and I click the download button the chart with the data series is downloaded.
If the chart code is in the button-click event and I click the download button the chart without the data series is downloaded.

Thank you.