public class ConstantLineCollection : ChartElementNamedCollection, IEnumerable<IConstantLine>, IEnumerable
Public Class ConstantLineCollection Inherits ChartElementNamedCollection Implements IEnumerable(Of IConstantLine), IEnumerable
Each axis (in particular, an axis of the AxisX or AxisY type) can hold a collection of constant lines which can be accessed via the Axis2D.ConstantLines property and is represented by the ConstantLineCollection class. The properties and methods exposed by the ConstantLineCollection class can be used to perform common collection operations such as adding new or deleting existing items. Each collection item is represented by a ConstantLine object. Individual constant lines can be accessed either using indexer notation or by their names using specific methods of the collection.
For more information, refer to Constant Lines.
This example demonstrates how a constant line can be created and customized at runtime.
Since constant lines belong to a diagram's axis, it's first required to cast your diagram object to the appropriate diagram's type. After that, it's possible to access axes and manage their constant lines collection.
// Cast the chart's diagram to the XYDiagram type, to access its axes. XYDiagram diagram = (XYDiagram)chartControl1.Diagram; // Create a constant line. ConstantLine constantLine1 = new ConstantLine("Constant Line 1"); diagram.AxisY.ConstantLines.Add(constantLine1); // Define its axis value. constantLine1.AxisValue = 7; // Customize the behavior of the constant line. constantLine1.Visible = true; constantLine1.ShowInLegend = true; constantLine1.LegendText = "Some Threshold"; constantLine1.ShowBehind = false; // Customize the constant line's title. constantLine1.Title.Visible = true; constantLine1.Title.Text = "Constant Line Title"; constantLine1.Title.TextColor = Color.Red; constantLine1.Title.Antialiasing = false; constantLine1.Title.Font = new Font("Tahoma", 14, FontStyle.Bold); constantLine1.Title.ShowBelowLine = true; constantLine1.Title.Alignment = ConstantLineTitleAlignment.Far; // Customize the appearance of the constant line. constantLine1.Color = Color.Red; constantLine1.LineStyle.DashStyle = DashStyle.Dash; constantLine1.LineStyle.Thickness = 2;
' Cast the chart's diagram to the XYDiagram type, to access its axes. Dim diagram As XYDiagram = CType(chartControl1.Diagram, XYDiagram) ' Create a constant line. Dim constantLine1 As New ConstantLine("Constant Line 1") diagram.AxisY.ConstantLines.Add(constantLine1) ' Define its axis value. constantLine1.AxisValue = 7 ' Customize the behavior of the constant line. constantLine1.Visible = True constantLine1.ShowInLegend = True constantLine1.LegendText = "Some Threshold" constantLine1.ShowBehind = False ' Customize the constant line's title. constantLine1.Title.Visible = True constantLine1.Title.Text = "Constant Line Title" constantLine1.Title.TextColor = Color.Red constantLine1.Title.Antialiasing = False constantLine1.Title.Font = New Font("Tahoma", 14, FontStyle.Bold) constantLine1.Title.ShowBelowLine = True constantLine1.Title.Alignment = ConstantLineTitleAlignment.Far ' Customize the appearance of the constant line. constantLine1.Color = Color.Red constantLine1.LineStyle.DashStyle = DashStyle.Dash constantLine1.LineStyle.Thickness = 2