C#

public class DoubleBufferPanel : Panel 
{ 
    public DoubleBufferPanel() 
    { 
        this.SetStyle(
            ControlStyles.AllPaintingInWmPaint |
            ControlStyles.UserPaint |
            ControlStyles.DoubleBuffer |
            ControlStyles.ResizeRedraw, true);
        this.UpdateStyles();
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);
        using (Pen pen = new Pen(Color.Black))
        {
            e.Graphics.DrawLine(pen, 0, 0, 10, 10);
        }
    }
}

Swetha Srinivasan wrote:

i want to check if the file is already open or not

MessageBox.Show(((Button)sender).Name + " Who raised this event?");

Button b = sender as Button;
if (b != null)
   {
   MessageBox.Show(b.Name + " Who raised this event?");
   }

if (sender is Button)
{
    Button button = sender as Button;
    // ...
}

Abdul Rahman Hamidy wrote:

does this application runs prior logging to my computer?

Abdul Rahman Hamidy wrote:

what I want is that when the logon screan appears this application should run at background whether i login or not.
any ideas or suggestions?

Christian Graus wrote:

I don't think anything runs prior to login, except the gina.dll that handles login.