Show all series' values in stacked bars mouseover (ASP.NET CHART)

I'm using the asp.net Chart control to present a stacked bars chart.

I can create a mouseover custom tooltip using this code:

series.MapAreaAttributes = "onmouseover=\"showTooltip('#VALY');\开发者_JAVA技巧"";

... which works fine. But I can't seem to find a way to show the rest of the values for the other series in that column.

Example: I have 2 series (Paid and Unpaid) making up a single column in the chart. When I mouseover any of the series, I want to show both the value of the moused-over series, but also the other series contained in that particular stacked column.

Can anyone point me in the right direction?

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We're also using stacked bar charts - we have click through functionality, for users to drill into the data making up each point in each series : we use something like this on each data point.

series.Points[index].MapAreaAttributes = "onclick=\"window.opener.location=this.href;window.opener.focus();return false;\"";