C# Classes Used in Charts

DataPoint Class

An instance of the DataPoint Class represents one data point in the DataPointCollection class. Typically we have an X value and a Y value; for some kinds of charts, there may be more than one Y value.

This is fundamentally a kind of list or array.

A common constructor takes two arguments, the X and Y values.

Properties:

• XValue
• YValues
• Color

DataPointCollection Class

A DataPointCollection object is a collection of DataPoints. It is found as the Points property of a Series object.

Properties:

• Count = the number of DataPoints in the collection
• Item[int N] = the Nth DataPoint

(and more).

Methods:

• public int AddXY(double X, double Y)

  This adds a DataPoint with the specified X and Y values; it returns the subscript where it was added (at the end of the collection).

• public int AddY(double Y)

  This adds a DataPoint with the specified Y value; it returns the subscript where it was added (at the end of the collection). The X value is apparently always 0.

• public void Clear()

  This empties the DataPoint Collection.

• protected override RemoveItem(int N)

  This removes Item[N].

Series Class

The Series class stores a DataPointCollection and a variety of Series attributes. It is a member of a SeriesCollection.

Properties:

• Points = the DataPointCollection for this Series
• ChartType = the type of chart desired (such as pie or column or bar), a member of the SeriesChartType enumeration.
• ChartArea = name of the ChartArea object involved

(and many, many more).

SeriesCollection Class

This is a collection of Series objects. We can have multiple series plotted on one chart (typically in different colors).

ChartArea Class

A chart area is represented by a ChartArea class object and ChartArea objects are stored in the ChartAreaCollection class.