4

I am drawing a curve in Zedgraph like this:

GraphPane myPane = zgc.GraphPane;
PointPairList list1 = new PointPairList();
for(int i =0; i<10; i++)
    list1.Add(i,i);            
LineItem myCurve = myPane.AddCurve("Title",
          list1, Color.Red, SymbolType.None);        

zgc.AxisChange();
zgc.Refresh();

How can I display a cursor (or any other graphic object) at a certain x, y point on myCurve like this:

SetCursor(myCurve, list1[3]);
Nikolay Kostov
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tomfox66
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2 Answers2

2

Knowing specific point of your curve you can use GraphPane.GeneralTransform(...) method

So using following code:

var myPoint = myCurve[3];
var screenPoint = myPane.GeneralTransform(myPoint.X, myPoint.Y, CoordType.AxisXYScale);

would give you coordinates transformed to specific point on screen (in pixels).

Then you need to find some higher-level method (probably in windows forms...) that would move your cursor to that point.

Gacek
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1

Here is a simple and more efficient example to create a cross cursor wich is part of the objects collection of the graph so you can operate zooming, printing on it. It add two "LineObj" in the "GraphObjList" collection. The code : Put a cursor at the 10th point of the first curve

    Dim myPane As GraphPane = zg1.GraphPane    
    Dim myPoint As PointPair = myPane.CurveList.Item(0).Points(10)
    Dim CurseurV1 As New LineObj(Color.Blue, myPoint.X,myPane.YAxis.Scale.Min, myPoint.X, myPane.YAxis.Scale.Max)

    CurseurV1.Line.Width = 0.5
    myPane.GraphObjList.Add(CurseurV1)

    Dim CurseurH1 As New LineObj(Color.Blue, myPane.XAxis.Scale.Min,myPoint.Y, myPane.XAxis.Scale.Max, myPoint.Y)
    CurseurH1.Line.Width = 1
    myPane.GraphObjList.Add(CurseurH1)

It's done : you'd have a blue "cross" cursor on your graphe using ZedGraph.dll Version 5.1.2.878.

Gilles5678
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