MouseMove Event in Form

Question

I want to be able to draw Graphics to the Form Window instead of a picturebox. But it doesn't seem that the form window captures the mousemove event.

namespace CollisionTest
    {
        public partial class Form1 : Form
        {
            private Graphics paper;
            private Pen pen;

            public Form1()
            {
                InitializeComponent();
                //paper = pictureBox1.CreateGraphics();
                paper = this.CreateGraphics();
                pen = new Pen(Color.Blue);
                pen.Width = 5;
                this.MouseMove += new System.Windows.Forms.MouseEventHandler(Form1_MouseMove);
            }
            private void Form1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
            {
                paper.Clear(Form1.ActiveForm.BackColor);
                paper.DrawRectangle(pen, e.X + 10, this.Height - 20, 50, 10);
            }
        }
    }

Answer 1

paper.Clear method Clears the entire drawing surface and fills it with the specified background color.

so when you move your mouse you first clear the graphic object and draw something so you cant see anything. test with removing :

paper.Clear(Form1.ActiveForm.BackColor);

from your code

Answer 2

Looks like you want a "pong paddle" going across the bottom of your form?

Just change this.Height to this.ClientRectangle.Height:

public partial class Form1 : Form
{

    private Pen pen;
    private Graphics paper;

    public Form1()
    {
        InitializeComponent();
        pen = new Pen(Color.Blue, 5);
        paper = this.CreateGraphics();
        this.MouseMove += new System.Windows.Forms.MouseEventHandler(Form1_MouseMove);
    }

    private void Form1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
    {
            paper.Clear(this.BackColor);
            paper.DrawRectangle(pen, e.X + 10, this.ClientRectangle.Height - 20, 50, 10);
    }

}