Problème pour dessiner un rectangle

Bonjour,

J'ai copié collé le code suivant de MSDN afin de dessiner un rectangle. Lorsque j'exécute le programme rien ne se passe lorsque j'appuie sur les boutons de la souris. J'ai fait également l'expérience sans événement de la souris et même résultats.

Avez-vous une idée pourquoi?

Code:

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using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
 
namespace ShemaBlockBuilder
{
    public partial class Form1 : Form
    {
 
        private Rectangle RcDraw;
        private float PenWidth = 5;
 
        private void Form1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
        {
 
            // Determine the initial rectangle coordinates...
 
            RcDraw.X = e.X;
            RcDraw.Y = e.Y;
 
        }
 
        private void Form1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)
        {
 
            // Determine the width and height of the rectangle...
 
            if (e.X < RcDraw.X)
            {
                RcDraw.Width = RcDraw.X - e.X;
                RcDraw.X = e.X;
            }
            else
            {
                RcDraw.Width = e.X - RcDraw.X;
            }
 
            if (e.Y < RcDraw.Y)
            {
                RcDraw.Height = RcDraw.Y - e.Y;
                RcDraw.Y = e.Y;
            }
            else
            {
                RcDraw.Height = e.Y - RcDraw.Y;
            }
 
            // Force a repaint of the region occupied by the rectangle...
 
            this.Invalidate(RcDraw);
 
        }
 
        private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
        {
 
            // Draw the rectangle...
 
            e.Graphics.DrawRectangle(new Pen(Color.Blue, PenWidth), RcDraw);
 
        }
 
 
        public Form1()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
 
        }
    }
}

Bonjour acheo.
En C# n'oublie jamais de creer les handlers d'event quand tu fais du copier-coller de code car ils n'existent pas ce qui explique l'absence de reaction du form....

Code:

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using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
 
namespace GrilleCSharp
{
    public partial class Form4 : Form
    {
        private Rectangle RcDraw;
        private float PenWidth = 5;
        public Form4()
        {
            InitializeComponent();
            //ajoute les handlers du mouse
            this.MouseDown+=new MouseEventHandler(Form4_MouseDown);  
            this.MouseUp += new MouseEventHandler(Form4_MouseUp); 
        }
 
        private void Form4_Load(object sender, EventArgs e)
        {
 
        }
 
        private void Form4_MouseDown(object sender, MouseEventArgs e)
        {
            // Determine the initial rectangle coordinates...
 
            RcDraw.X = e.X;
            RcDraw.Y = e.Y;
        }
 
        private void Form4_MouseUp(object sender, MouseEventArgs e)
        {
            // Determine the width and height of the rectangle...
 
            if (e.X < RcDraw.X)
            {
                RcDraw.Width = RcDraw.X - e.X;
                RcDraw.X = e.X;
            }
            else
            {
                RcDraw.Width = e.X - RcDraw.X;
            }
 
            if (e.Y < RcDraw.Y)
            {
                RcDraw.Height = RcDraw.Y - e.Y;
                RcDraw.Y = e.Y;
            }
            else
            {
                RcDraw.Height = e.Y - RcDraw.Y;
            }
 
            // Force a repaint of the region occupied by the rectangle...
 
            this.Invalidate(RcDraw);
        }
 
        private void Form4_Paint(object sender, PaintEventArgs e)
        {
            // Draw the rectangle...
 
            e.Graphics.DrawRectangle(new Pen(Color.Blue, PenWidth), RcDraw);
 
 
        }
 
 
 
    }
}

bon code....................

merci