2D Graphics Visual C++ .NET

using namespace System;
  using namespace System::ComponentModel;
  using namespace System::Collections;
  using namespace System::Windows::Forms;
  using namespace System::Data;
  using namespace System::Drawing;
  public ref class Form1 : public System::Windows::Forms::Form
  {
  public:
    Form1(void)
    {
            this->SuspendLayout();
            this->AutoScaleDimensions = System::Drawing::SizeF(6, 13);
            this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
            this->ClientSize = System::Drawing::Size(341, 273);
            this->Name = L"Form1";
            this->Text = L"Millimeter Unit of measure Origin (20,20)";
            this->Paint += 
                gcnew System::Windows::Forms::PaintEventHandler(this, 
                                                         &Form1::Form1_Paint);
            this->ResumeLayout(false);
    }
 
        System::Void Form1_Paint(System::Object^ sender, 
                                System::Windows::Forms::PaintEventArgs^ e)
        {
            Graphics ^g = e->Graphics;
 
            // Draw a rectangle before unit of measure and origin change
            g->DrawRectangle(Pens::Black, 5, 5, 50, 20);
 
            // Draw same rectangle after change
            g->PageUnit = GraphicsUnit::Millimeter;
           g->TranslateTransform(20,20);
           g->DrawRectangle(Pens::Black, 5, 5, 50, 20);
        }
  };
[STAThreadAttribute]
int main(array ^args)
{
  Application::Run(gcnew Form1());
  return 0;
}