If you are going to change the DataSource of the chart you can change other settings (e.g. the DataLabelsField of the x-axis) at the same time. This approach is used to achieve the drilldown in this demo, and I believe it is quite close to what you are looking for: http://demos.telerik.com/aspnet-ajax/htmlchart/examples/drilldownchart/defaultcs.aspx
. It shows how you can configure settings for the chart based on the datasource fields. Once the chart has correct settings it will render properly on the client without additional JS code.
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