C#

 private void Form1_MouseUp(object sender, System.Windows.Forms.MouseEventArgs e)<br />
{<br />
<br />
  this.X2=e.X;<br />
  this.Y2=e.Y;<br />
<br />
  Graphics dc = this.CreateGraphics();<br />
  Pen BluePen = new Pen(Color.Blue, 3);<br />
  dc.DrawRectangle(BluePen, X1,Y1,X2-X1,Y2-Y1);<br />
<br />
  Brush obj_brush=Brushes.Blue;<br />
<br />
  dc.FillRectangle(obj_brush,X1,Y1,X2-X1,Y2-Y1);<br />
<br />
<br />
<br />
}