Before answering your questions let me explain you the way RadChart's XAxis values can be set. As XAxis expects it's items to be of type double
you can't directly set DateTime values as XValue.
The DateTime values should be converted to their OLE Automation equivalents using theToOADate()
method provided by the Framework.
If you want to plot not only values (e.g. number of sales, etc.), but also categories (e.g. months of the year, units, people, etc.) you should use XCategory
as it treats the data as a sequence of non-numerical text labels.
To your question:
(Double) - ItemTooltipFormat can be set as I showed you in my previous post.
(String) - as if your Date values were represented by XCategory. In this case the ItemTooltipFormat can be set as my co-worker Evgeni suggested in this forum post
. Happily to you this suggestion uses XAML only to format the XCategory.
(DateTime) - you should convert the DateTime to OADate() and then set the ItemTooltipFormat as written in 1).
I hope this information helps!
All the best,
the Telerik team