Overriding RadChartView rendering

Hello Neil,

Thank you for your interest in our RadChartView for WinForms.

The control provides a way to create a custom renderer to customize its elements as demonstrated in this Custom Rendering help article. The grid lines are represented by the CartesianGridDrawPart. You could override the InitializeGrid() method and add your own implementation of CartesianGridDrawPart. The magic happens in the Draw() method.

private void radChartView1_CreateRenderer(object sender, ChartViewCreateRendererEventArgs e)
{
    e.Renderer = new CustomCartesianRenderer(e.Area as CartesianArea);
}

public class CustomCartesianRenderer : CartesianRenderer
    {
        public CustomCartesianRenderer(CartesianArea area)
        : base(area)
        { }
        protected override void InitializeGrid()
        {
            //base.InitializeGrid();
            if (this.Area.Grid is CartesianGrid)
            {
                this.DrawParts.Add(new CustomCartesianGridDrawPart((CartesianGrid)this.Area.Grid, this));
            }
        }        
    }
    public class CustomCartesianGridDrawPart : DrawPart<CartesianGrid>
    {
        public CustomCartesianGridDrawPart(CartesianGrid grid, IChartRenderer renderer)
            : base(grid, renderer)
        { }
        public override void Draw()
        {
           // custom logic
        }
    }

However, upon checking the source code to propose a suitable solution, the base logic of the Draw() method contains a lot of internal classes which makes it almost impossible to modify the source code. You will have to create the logic which draws the grid lines from scratch. What I can suggest instead is to place Marked Zone annotation and the area in which you want to hide the grid. The annotation will be placed on top of the grid. Here is what I have in mind. You can observe how the grid lines under 0 are not visible.

You can find the sample project which I created to test your scenario. I hope that this approach will work for you.

Regards,
Dinko | Tech Support Engineer
Progress Telerik