Hi Sweta,

To achieve this appearance of line styles you need to modify the line color and width as well as marker appearance and shape - the following code shows how to achieve that:

 NChart chart = nChartControl1.Charts[0];

  NLineSeries line = new NLineSeries();

  line.MarkerStyle.Visible = true;
  line.MarkerStyle.PointShape = PointShape.Pyramid;
  line.BorderStyle.Color = Color.Red;
  line.MarkerStyle.FillStyle = new NColorFillStyle(Color.Red);
  line.MarkerStyle.BorderStyle.Width = new NLength(0);
  line.DataLabelStyle.Visible = false;

  line.Values.Add(10);
  line.Values.Add(30);
  line.Values.Add(20);

  chart.Series.Add(line);

We hope this helps - let us know if you meet any problems or have any questions.

Best Regards,
Nevron Support Team