private void Load_file_Click(object sender, EventArgs
 e)
         {
             if ((OpenFileDialog1.ShowDialog() != DialogResult.OK)) return;
             //CADImage.CreateImageByExtension detects format by the extension
 specified in the argument. 
             //The correct class for any supported format will be used
 automatically. We recommend to
             //create a new drawing object with CADImage.CreateImageByExtension
 if import from the existed
             //file/stream is required.
             CADImage vDrawing =
 CADImage.CreateImageByExtension(OpenFileDialog1.FileName);
             vDrawing.LoadFromFile(OpenFileDialog1.FileName);
             // adjusting of the visualization sizes to the control area:
 	        RectangleF vRect;
 	        double vRatio = (double)(vDrawing.AbsHeight * Image1.ClientSize.Width)
 / (vDrawing.AbsWidth * Image1.ClientSize.Height);
 	        if (vRatio > 1)
                 vRect = new RectangleF(0, 0, (float)(Image1.ClientSize.Width /
 vRatio), (float)Image1.ClientSize.Height);
 	        else
                 vRect = new RectangleF(0, 0, (float)Image1.ClientSize.Width,
 (float)(Image1.ClientSize.Height * vRatio));
             //-----------------------------------------------
             vDrawing.Draw(Image1.CreateGraphics(), vRect);
         }