Question

I have a graphical application in which I move a graphic object with the mouse.

In some conditions, the object stops moving. I need then to stop moving the mouse cursor too.

Is it possible? MousePosition property seems to be in ReadOnly.

Eg.

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_MouseMove(object sender, MouseEventArgs e)
    {
        if (e.X > 100)
        {
            Cursor.Position = new Point(100, Cursor.Position.Y);
        }
    }
}

EDIT, second version, works, but the cursor is not “stable” – flickering:

    private void Form1_MouseMove(object sender, MouseEventArgs e)
    {
        if (e.X > 100)
        {
            Point mousePosition = this.PointToClient(Cursor.Position);
            mousePosition.X = 100;
            Point newScreenPosition = this.PointToScreen(mousePosition);
            Cursor.Position = newScreenPosition;
        }
    }

Answer 1

You could use the ClipCursor function via PInvoke. If the bouding rectangle is small enough, the mouse will not move.

---

EDIT

An example:

[StructLayout(LayoutKind.Sequential, Pack=1)]
public struct RECT {
    public int left;
    public int top;
    public int right;
    public int bottom;
};


public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    [DllImport("user32.dll")]
    static extern bool ClipCursor([In()]ref RECT lpRect);

    [DllImport("user32.dll")]
    static extern bool ClipCursor([In()]IntPtr lpRect);


    private bool locked = false;

    private void button1_Click(object sender, EventArgs e)
    {

        if (locked) {
            ClipCursor(IntPtr.Zero );
        }
        else {
            RECT r;

            Rectangle t = new Rectangle(0, 0, 100, this.ClientSize.Height);
            t = this.RectangleToScreen(t);

            r.left = t.Left;
            r.top = t.Top;
            r.bottom = t.Bottom;
            r.right = t.Right;

            ClipCursor(ref r);
        }

        locked = !locked;

    }
    private void Form1_Load(object sender, EventArgs e)
    {

    }
}