Painting in a panel

I was wondering how I could draw in a Panel. If I create a Panel like

  Panel panel = new Panel();

panel.Width = 1000;

panel.Height = 750;

this.Controls.Add(_panel);
 

In Windows Forms, I could call the PaintEvent but there is not PaintEvent in asp.net is there? So how do I draw lines and such on a web form? Also the Panel control in the windows forms has a location property but the Panel web control does not?
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