.NET Examples: Column Chart

This exercise applies the concepts reviewed for drawing shapes. In this case, we will draw some rectangles to product a (vertical) column chart.

1. Start a new Windows Forms Application named WeeklySales1
2. Set the form's Icon to Drive:\Program Files\Microsoft Visual Studio .NET 2003\Common7\Graphics\icons\Office\GRAPH07.ICO
3. Design the form as follows:
    

   Control Name Text Other Properties Label   Monday   Label   Tuesday   Label   Wednesday   Label   Thursday   Label   Friday   TextBox txtMonday 12000 TextAlign: Right TextBox txtTuesday 11000 TextAlign: Right TextBox txtWednesday 8500 TextAlign: Right TextBox txtThursday 16800 TextAlign: Right TextBox txtFriday 17500 TextAlign: Right Button Generate btnGenerate

4. Double-click an unoccupied area on the form and implement its Load event as follows:
    

   . . . No Change namespace WeeklySales1a { /// <summary> /// Summary description for Form1. /// </summary> public class Form1 : System.Windows.Forms.Form { . . . No Change /// <summary> /// Required designer variable. /// </summary> private System.ComponentModel.Container components = null; Graphics graphDrawingArea; Bitmap bmpDrawingArea; . . . No Change #region Windows Form Designer generated code /// <summary> /// Required method for Designer support - do not modify /// the contents of this method with the code editor. /// </summary> private void InitializeComponent() { . . . No Change } #endregion /// <summary> /// The main entry point for the application. /// </summary> [STAThread] static void Main() { Application.Run(new Form1()); } private void Form1_Load(object sender, System.EventArgs e) { bmpDrawingArea = new Bitmap(Width, Height); graphDrawingArea = Graphics.FromImage(bmpDrawingArea); } } }

5. Return to the form and click an empty area on it. In the Properties window, click the Events button
6. Double-click the Paint field and implement its event as follows:
    

   private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e) { e.Graphics.DrawImage(bmpDrawingArea, 0, 0); }

7. Double-click the Generate button and implement its Click event as follows:
    

   private void btnGenerate_Click(object sender, System.EventArgs e) { int monday = int.Parse(this.txtMonday.Text) / 100; int tuesday = int.Parse(this.txtTuesday.Text) / 100; int wednesday = int.Parse(this.txtWednesday.Text) / 100; int thursday = int.Parse(this.txtThursday.Text) / 100; int friday = int.Parse(this.txtFriday.Text) / 100; graphDrawingArea.Clear(this.BackColor); graphDrawingArea.DrawRectangle(new Pen(Color.Red), this.txtMonday.Left+5, 280-monday, 40, monday); graphDrawingArea.DrawRectangle(new Pen(Color.Blue), this.txtTuesday.Left+5, 280-tuesday, 40, tuesday); graphDrawingArea.DrawRectangle(new Pen(Color.Fuchsia), this.txtWednesday.Left+5, 280-wednesday, 40, wednesday); graphDrawingArea.DrawRectangle(new Pen(Color.Brown), this.txtThursday.Left+5, 280-thursday, 40, thursday); graphDrawingArea.DrawRectangle(new Pen(Color.Turquoise), this.txtFriday.Left+5, 280-friday, 40, friday); graphDrawingArea.DrawRectangle(new Pen(Color.Black), 10, 280, Width - 30, 1); Invalidate(); }

8. Execute the application and test the form
    
    
9. After using it, close the form
10. Change the implementation of the Click event of the Generate button as follows:
     

    private void btnGenerate_Click(object sender, System.EventArgs e) { int monday = int.Parse(this.txtMonday.Text) / 100; int tuesday = int.Parse(this.txtTuesday.Text) / 100; int wednesday = int.Parse(this.txtWednesday.Text) / 100; int thursday = int.Parse(this.txtThursday.Text) / 100; int friday = int.Parse(this.txtFriday.Text) / 100; graphDrawingArea.Clear(this.BackColor); graphDrawingArea.FillRectangle(new SolidBrush(Color.Red), this.txtMonday.Left+5, 280-monday, 40, monday); graphDrawingArea.DrawRectangle(new Pen(Color.Black), this.txtMonday.Left+5, 280-monday, 40, monday); graphDrawingArea.FillRectangle(new SolidBrush(Color.Blue), this.txtTuesday.Left+5, 280-tuesday, 40, tuesday); graphDrawingArea.DrawRectangle(new Pen(Color.Black), this.txtTuesday.Left+5, 280-tuesday, 40, tuesday); graphDrawingArea.FillRectangle(new SolidBrush(Color.Fuchsia), this.txtWednesday.Left+5, 280-wednesday, 40, wednesday); graphDrawingArea.DrawRectangle(new Pen(Color.Black), this.txtWednesday.Left+5, 280-wednesday, 40, wednesday); graphDrawingArea.FillRectangle(new SolidBrush(Color.Brown), this.txtThursday.Left+5, 280-thursday, 40, thursday); graphDrawingArea.DrawRectangle(new Pen(Color.Black), this.txtThursday.Left+5, 280-thursday, 40, thursday); graphDrawingArea.FillRectangle(new SolidBrush(Color.Turquoise), this.txtFriday.Left+5, 280-friday, 40, friday); graphDrawingArea.DrawRectangle(new Pen(Color.Black), this.txtFriday.Left+5, 280-friday, 40, friday); graphDrawingArea.DrawRectangle(new Pen(Color.Black), 10, 280, Width - 30, 1); Invalidate(); }

11. Execute the application and test the form
     
     
12. After using it, close the form