problem with draw string

public void DrawStringPointF(PaintEventArgs e) { // Create string to draw. String drawString = "Sample Text"; // Create font and brush. Font drawFont = new Font("Arial", 16); SolidBrush drawBrush = new SolidBrush(Color.Black); // Create point for upper-left corner of drawing. PointF drawPoint = new PointF(150.0F, 150.0F); // Draw string to screen. e.Graphics.DrawString(drawString, drawFont, drawBrush, drawPoint); } how can i retrieve the draw string text if i given the object drawn that means how can i know what is the text in the rectangular if i given the rectangular draw.thank you.