How do I "zoom" to a page without using PDFView (for use in a web site)?

Q: In, how to apply "zoom" to a page without using PDFView ?
As we may use the zoom factor from the c# code ? Any example ?
A: Assuming that you are dynamically converting PDF pages to images
using PDFDraw class (
samplecode.html#PDFDraw) you can use larger values of DPI (Dots Per
Inch) to generate higher resolution images (e.g.
pdfdraw.SetDPI(200)). You can also ‘zoom’ into specific parts of the
page without increasing the size of the overall image by cropping the
page (e.g. using page.SetCropBox(box)) and by increasing DPI.