Formatting tooltip on Zedgraph

c#, tooltip, zedgraph

Solution

There are a couple of different ways of doing this.

Option 1 is to use the PointPair's Tag property when setting up your data. If the Tag is a string, it will be displayed as a tooltip for the point.

PointPair pp = new PointPair(....);
pp.Tag = "This is a custom tooltip";

Option 2 is to subscribe to the graph control's PointValueEvent and provide a custom value in your event handler.

graph.PointValueEvent += OnPointValueRequested;
...
private string OnPointValueRequested(object sender, GraphPane pane, CurveItem curve, int pointIndex)
{
    PointPair point= curve[pointIndex];
    string tooltip = String.Format("({0}, {1})", point.X point.Y);
    return tooltip;
}

Also keep in mind that there is a bug with tooltip CPU usage on Vista and above. You may need to patch your copy of ZedGraph to fix it if you haven't already done so.

Problem

I want to format my tool tip that I used to display graph and point information on PointValueEvent on Zedgraph. I know how to format normal tool tip but in this case zedgraph doesn't have tool tip property. Point value event automatically shows tool tip. How to formatt that tool tip?

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