Creating Bar Chart using C#

Creating Bar Chart in windows using C#
Introduction-
For making bar chart we will make use of ‘DrawRectangle’ in built function. because we have to first create a big rectangle defining the boundary of bar graphs. Parameters of DrawRectangle is :

1. Pen – This defines the color and style of border
2. Rectangle – Rectangle object to be created

Rectangle(int x, int y, int width,int height)
X and y are the co-ordinates of top left corner of rectangle. Width and height are width and height of rectangle.

Height = (weight of current array element *height of outer rectangle )/ maximum weight.
X coordinate is incremented by width of bars everytime a new bar is created.

Y co-ordinate is calculated by the following formula:

y = y coordinate of outer rectangle + height of outer rectangle – height of bar 

Code for DrawBarChart

private void DrawBarChart(PaintEventArgs e, int[] alWeight) { int numberOfSections = alWeight.Length; int lengthArea = 330; int heightArea = 280; int topX = 20; int topY = 20; int maxWeight = MaxValue(alWeight); int[] height = new int[numberOfSections]; int total = SumOfArray(alWeight); Random rnd = new Random(); SolidBrush brush = new SolidBrush(Color.Aquamarine); Pen pen = new Pen(Color.Gray); Rectangle rec = new Rectangle(topX, topY, lengthArea, heightArea); e.Graphics.DrawRectangle(pen, rec); pen.Color = Color.Black; int smallX = topX; int smallY = 0; int smallLength = (lengthArea / alWeight.Length); int smallHeight = 0; for (int i = 0; i < numberOfSections; i++) { brush.Color = Color.FromArgb(rnd.Next(200, 255), rnd.Next(255), rnd.Next(255), rnd.Next(255)); smallHeight = ((alWeight[i] * heightArea) / maxWeight); smallY = topY + heightArea - smallHeight; Rectangle rectangle = new Rectangle (smallX, smallY, smallLength, smallHeight); e.Graphics.DrawRectangle(pen, rectangle); e.Graphics.FillRectangle(brush, rectangle); brush.Color = Color.FromKnownColor(KnownColor.Black); e.Graphics.DrawRectangle(pen, rectangle); smallX = smallX + smallLength; } }