A Series of Rectangles

This method requires an array of Rectangle or RectangleF values. When executed, it draws individual rectangles using each member of the array as its own rectangle. Here is an example:

System::Void Form1_Paint(System::Object^  sender,
			 System::Windows::Forms::PaintEventArgs^  e)
{
    Pen ^ penCurrent = gcnew Pen(Color::Red);
    array<Rectangle> ^ Rect = { Rectangle(20,  20, 120, 20),
	                        Rectangle(20,  50, 120, 30),
		                Rectangle(20,  90, 120, 40),
		                Rectangle(20, 140, 120, 60) };

    e->Graphics->DrawRectangles(penCurrent, Rect);
}

This would produce:

1. Start a new Windows Forms Application named YearlySales1
2. Design the form as follows:
    

   Control Name Text GroupBox   Current Year's Sales Label   1st Qtr Label   2nd Qtr Label   3rd Qtr Label   4th Qtr TextBox txtCurrentQtr1 1200 TextBox txtCurrentQtr2 14500 TextBox txtCurrentQtr3 8500 TextBox txtCurrentQtr4 16800 Button Close btnClose GroupBox   Previous Year's Sales Label   1st Qtr Label   2nd Qtr Label   3rd Qtr Label   4th Qtr TextBox txtPreviousQtr1 10000 TextBox txtPreviousQtr2 11000 TextBox txtPreviousQtr3 12500 TextBox txtPreviousQtr4 15800 Button Generate btnGenerate Label   _________ Legend _________ Label lblCurYear This Year's Sales Label lblLastYear Last Year's Sales

3. Right-click the table and click View Code
4. Declare two variables as follows:
    

   private: /// <summary> /// Required designer variable. /// </summary> System::ComponentModel::Container * components; Graphics ^ graphDrawingArea; Bitmap ^ bmpDrawingArea;

5. Return to the form and double-click an unoccupied area of its body
6. Implement the event as follows:
    

   System::Void Form1_Load(System::Object^ sender, System::EventArgs^ e) { bmpDrawingArea = gcnew Bitmap(Width, Height); graphDrawingArea = Graphics::FromImage(bmpDrawingArea); }

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

   System::Void Form1_Paint(System::Object^ sender, System::Windows::Forms::PaintEventArgs^ e) { e->Graphics->DrawImage(bmpDrawingArea, 0, 0); }

9. Return to the form and double-click the Generate button
10. Implement the event as follows:
     

    System::Void btnGenerate_Click(System::Object^ sender, System::EventArgs^ e) { int curQtr1, curQtr2, curQtr3, curQtr4; int prvQtr1, prvQtr2, prvQtr3, prvQtr4; // Retrieve the values of the current year's sales try { curQtr1 = int::Parse(txtCurrentQtr1->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the first quater"); curQtr1 = 0; } try { curQtr2 = int::Parse(txtCurrentQtr2->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the second quater"); curQtr2 = 0; } try { curQtr3 = int::Parse(txtCurrentQtr3->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the third quater"); curQtr3 = 0; } try { curQtr4 = int::Parse(txtCurrentQtr4->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the fourth quater"); curQtr4 = 0; } // Create an array of Rectangle objects for the current year array<Rectangle> ^ rectCurrentYear = { Rectangle(this->txtCurrentQtr1->Left+20, 380-curQtr1, 40, curQtr1), Rectangle(this->txtCurrentQtr2->Left+20, 380-curQtr2, 40, curQtr2), Rectangle(this->txtCurrentQtr3->Left+20, 380-curQtr3, 40, curQtr3), Rectangle(this->txtCurrentQtr4->Left+20, 380-curQtr4, 40, curQtr4) }; // Retrieve the values of last year's sales try { prvQtr1 = int::Parse(txtPreviousQtr1->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the third quater"); prvQtr1 = 0; } try { prvQtr2 = int::Parse(txtPreviousQtr2->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the third quater"); prvQtr2 = 0; } try { prvQtr3 = int::Parse(txtPreviousQtr3->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the third quater"); prvQtr3 = 0; } try { prvQtr4 = int::Parse(txtPreviousQtr4->Text) / 100; } catch(FormatException ^) { MessageBox::Show(L"Invalid value for the third quater"); prvQtr4 = 0; } // Create an array of Rectangle objects for the previous year array<Rectangle> ^ rectPreviousYear = { Rectangle(this->txtPreviousQtr1->Left+30, 380-prvQtr1, 40, prvQtr1), Rectangle(this->txtPreviousQtr2->Left+30, 380-prvQtr2, 40, prvQtr2), Rectangle(this->txtPreviousQtr3->Left+30, 380-prvQtr3, 40, prvQtr3), Rectangle(this->txtPreviousQtr4->Left+30, 380-prvQtr4, 40, prvQtr4) }; // In case the user has changed the values, // erase the previous chart graphDrawingArea->Clear(this->BackColor); // Draw the chart for the previous year first to send it back graphDrawingArea->DrawRectangles(gcnew Pen(Color::Blue), rectPreviousYear); // Draw the chart for the current year in front graphDrawingArea->DrawRectangles(gcnew Pen(Color::Red), rectCurrentYear); // Draw the small rectangles of the legend graphDrawingArea->DrawRectangle(gcnew Pen(Color::Blue), this->lblCurYear->Left-30, this->lblCurYear->Top, 14, 10); graphDrawingArea->DrawRectangle(gcnew Pen(Color::Red), this->lblLastYear->Left-30, this->lblLastYear->Top, 14, 10); graphDrawingArea->DrawRectangle(gcnew Pen(Color::Black), 25, 380, Width - 220, 1); Invalidate(); }

11. Return to the form. Double-click the Close button and implement its Click event as follows:
     

    System::Void btnClose_Click(System::Object ^ sender, System::EventArgs ^ e) { Close(); }

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