Axis

An axis is a reference line measuring distances or angles in a coordinate system. One or more axis are contained in a plot area. A PlotArea will have one default x-axis (XAxis) and one default y-axis (YAxis). But a PlotArea is not limited to the default axis and can have multiple x-axis and y-axes.

Each of the different series types has a specific type of axis created by default, not the user. For example, the DateTimeAreaSeries, the DateTimeBarSeries, DateTimeColumnSeries, and DateTimeLineSeries all have a DateTimeXAxis and a NumericYAxis.

A PlotArea has a Series property that specifies a SeriesList. A SeriesList has an Add method, which creates the appropriate axis when adding a series to the SeriesList.

Axis By Series

The following table lists the series and the x-axis and y-axis associated with the series.

XAxis

An x-axis (specified by the XAxis class) is the horizontal axis of a two-dimensional Cartesian coordinate system. To change an XAxis position - on the plot area's bottom by default - use the XAxisAnchorType enumeration.

To specify a series-specific type of x-axis, use code similar to the following (using the appropriate XAxis subclass depending upon the series).

NumericXAxis axis = barSeries.XAxis;
DateTimeXAxis axis2 = dateTimeSeries.XAxis;

Dim MyAxis As NumericXAxis = MyBarSeries.XAxis   
Dim MyAxis2 AS DateTimeXAxis = MyDateTimeSeries.XAxis

The XAxis has the following sub-classes for each of the different x-axis types (see table above).

• NumericXAxis
• DateTimeXAxis
• PercentageXAxis
• IndexedXAxis

XAxis Properties

The XAxis class has the following properties inherited by all the specific XAxis subclasses.

It is unnecessary to set maximum or minimum values or intervals for an axis, as the provided data calculate these values. However, the x-axis subclasses also have Min, Max, and Interval properties for specifying the minimum and maximum series values. But be sure to set the subclass label's AutoLabels property to False.

myAxis.Min = 185;
myYAxis.Max = 235;
myYAxis.Interval = 10;
myYAxis.Labels.AutoLabels = False;

NumericXAxis

The NumericXAxis uses numeric data, displays the values using NumericXAxisLabels, and places the NumericXAxis on the plot area. See the table above for a listing showing the series that use a NumericXAxis.

DateTimeXAxis

The DateTimeXAxis uses date and time data, displays the values using DateTimeXAxisLabels, and places the DateTimeXAxis on the plot area. See the table above for a listing showing the series that use a DateTimeXAxis.

PercentageXAxis

The PercentageXAxis uses numeric data in percentage format, displays the values using PercentageXAxisLabels, and places the PercentageXAxis on the plot area. See the table above for a listing showing the series that use a PercentageXAxis.

IndexedXAxis

The IndexedXAxis uses non-numeric data, displays the values using IndexedXAxisLabel, and places the IndexedXAxis on the plot area. See the table above for a listing showing the series that uses an IndexedXAxis.

YAxis

A y-axis (specified by the YAxis class) is the vertical axis of a two-dimensional Cartesian coordinate system. To change the y-axis - to the left of the plot area by default - use the YAxisAnchorType enumeration.

myYAxis.AnchorType = YAxisAnchorType.Left;

To specify a specific type of y-axis from a series, use code similar to the following (using the appropriate YAxis subclass depending upon the series).

IndexedYAxis yAxis = barSeries.YAxis;
NumericYAxis yAxis2 = dateTimeSeries.YAxis;

Dim MyYAxis As IndexedYAxis = MyBarSeries.YAxis  
Dim MyYAxis2 As NumericYAxis = MyDateTimeSeries.YAxis;

The YAxis has the following sub-classes for each y-axis type (see table above).

• NumericYAxis
• DateTimeYAxis
• PercentageYAxis
• IndexedYAxis

YAxis Properties

The YAxis class has the following properties inherited by all the specific YAxis subclasses.

It is unnecessary to set maximum or minimum values or intervals for an axis, as the provided data calculate these values. However, the y-axis subclasses also have Min, Max, and Interval properties for specifying the minimum and maximum series values. But be sure to set the subclass label's AutoLabels property to False.

myAxis.Min = 185;
myYAxis.Max = 235;
myYAxis.Interval = 10;
myYAxis.Labels.AutoLabels = False;

NumericYAxis

The NumericYAxis uses numeric data, displays the values using NumericYAxisLabels, and places the NumericYAxis on the plot area. See the table above for a listing showing the series that use a NumericYAxis.

DateTimeYAxis

The DateTimeYAxis uses date and time data, displays the values using DateTimeYAxisLabels, and places the DateTimeYAxis on the plot area. See the table above for a listing showing the series that use a DateTimeYAxis.

PercentageYAxis

The PercentageYAxis uses numeric data in percentage format, displays the values using PercentageYAxisLabels, and places the PercentageYAxis on the plot area. See the table above for a listing showing the series that use a PercentageYAxis.

IndexedYAxis

The IndexedYAxis uses non-numeric data, displays the values using IndexedYAxisLabels, and places the IndexedYAxis on the plot area. See the table above for a listing showing the series that uses an IndexedYAxis.