FlexChartでは、系列の数に応じて、チャートの左側または右側に、任意の数のY軸（３個以上も可）を設定できます。 同じ側（例えば、チャートの右側）に複数のY軸を設定することも可能です。

以下に、４つの系列を使用し、チャートの左・右にそれぞれ２本のY軸を設定するサンプルコードを記載します。



◎サンプルコード（VB）

Imports C1.Chart
Imports C1.Win.Chart

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        ' データの作成

        Dim dt As DataTable = New DataTable()
        dt.Columns.AddRange({
            New DataColumn("X", GetType(String)),
            New DataColumn("Y1", GetType(Integer)),
            New DataColumn("Y2", GetType(Integer)),
            New DataColumn("Y3", GetType(Integer)),
            New DataColumn("Y4", GetType(Integer))
        })
        dt.Rows.Add("A", 1, 40, 300, 2000)
        dt.Rows.Add("B", 2, 10, 400, 3000)
        dt.Rows.Add("C", 3, 20, 100, 4500)
        dt.Rows.Add("D", 4, 30, 200, 3500)
        dt.Rows.Add("E", 5, 10, 500, 4000)
        dt.AcceptChanges()

        ' シリーズの作成
        Dim series1 = New Series() With {
            .Name = "series1",
            .Binding = "Y1",
            .StackingGroup = 0
        }
        series1.AxisY = New Axis() With {
            .Position = Position.Left,
            .AxisLine = True,
            .Min = 0,
            .Max = 5,
            .Title = "シリーズ1"
        }

        Dim series2 = New Series() With {
            .Name = "series2",
            .Binding = "Y2",
            .ChartType = ChartType.LineSymbols,
            .StackingGroup = 0
        }
        series2.AxisY = New Axis() With {
            .Position = Position.Left,
            .AxisLine = True,
            .Min = 0,
            .Max = 50,
            .Title = "シリーズ2"
        }

        Dim series3 = New Series() With {
            .Name = "series3",
            .Binding = "Y3",
            .ChartType = ChartType.Spline,
            .StackingGroup = 0
        }
        series3.AxisY = New Axis() With {
            .Position = Position.Right,
            .AxisLine = True,
            .Min = 0,
            .Max = 500,
            .Title = "シリーズ3"
        }

        Dim series4 = New Series() With {
            .Name = "series4",
            .Binding = "Y4",
            .ChartType = ChartType.Scatter,
            .StackingGroup = 0
        }
        series4.AxisY = New Axis() With {
            .Position = Position.Right,
            .AxisLine = True,
            .Min = 0,
            .Max = 5000,
            .Title = "シリーズ4"
        }

        ' 棒グラフの作成
        FlexChart1.BindingX = "X"
        FlexChart1.ChartType = ChartType.Column
        FlexChart1.DataSource = dt
        FlexChart1.Stacking = Stacking.Stacked

        FlexChart1.Series.Clear()
        FlexChart1.Series.Add(series1)
        FlexChart1.Series.Add(series2)
        FlexChart1.Series.Add(series3)
        FlexChart1.Series.Add(series4)

        FlexChart1.Legend.Position = Position.Top
    End Sub
End Class

◎サンプルコード（C#）

using C1.Chart;
using C1.Win.Chart;

namespace _20220214d
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // データの作成
            var dt = new DataTable();
            dt.Columns.AddRange(new DataColumn[] {
                new DataColumn("X",typeof(String)),
                new DataColumn("Y1",typeof(Int32)),
                new DataColumn("Y2",typeof(Int32)),
                new DataColumn("Y3",typeof(Int32)),
                new DataColumn("Y4",typeof(Int32))
            });
            dt.Rows.Add("A", 1, 40, 300, 2000);
            dt.Rows.Add("B", 2, 10, 400, 3000);
            dt.Rows.Add("C", 3, 20, 100, 4500);
            dt.Rows.Add("D", 4, 30, 200, 3500);
            dt.Rows.Add("E", 5, 10, 500, 4000);
            dt.AcceptChanges();

            // シリーズの作成
            var series1 = new Series()
            {
                Name = "series1",
                Binding = "Y1",
                StackingGroup = 0,
                AxisY = new Axis()
                {
                    Position = Position.Left,
                    AxisLine = true,
                    Min = 0,
                    Max = 5,
                    Title = "シリーズ1"
                }
            };

            var series2 = new Series()
            {
                Name = "series2",
                Binding = "Y2",
                ChartType = ChartType.LineSymbols,
                StackingGroup = 1,
                AxisY = new Axis()
                {
                    Position = Position.Left,
                    AxisLine = true,
                    Min = 0,
                    Max = 50,
                    Title = "シリーズ2"
                }
            };

            var series3 = new Series()
            {
                Name = "series3",
                Binding = "Y3",
                ChartType = ChartType.Spline,
                StackingGroup = 2,
                AxisY = new Axis()
                {
                    Position = Position.Right,
                    Min = 0,
                    Max = 500,
                    Title = "シリーズ3"
                }
            };

            var series4 = new Series()
            {
                Name = "series4",
                Binding = "Y4",
                ChartType = ChartType.Scatter,
                StackingGroup = 3,
                AxisY = new Axis()
                {
                    Position = Position.Right,
                    Min = 0,
                    Max = 5000,
                    Title = "シリーズ4"
                }
            };

            // 棒グラフの作成
            flexChart1.BindingX = "X";
            flexChart1.ChartType = ChartType.Column;
            flexChart1.DataSource = dt;
            flexChart1.Stacking = Stacking.Stacked;

            flexChart1.Series.Clear();
            flexChart1.Series.Add(series1);
            flexChart1.Series.Add(series2);
            flexChart1.Series.Add(series3);
            flexChart1.Series.Add(series4);

            flexChart1.Legend.Position = Position.Top;
        }
    }
}