title: How to obtain the date information from a web page, using C#?
body: <p>I am currently writing a small crawler program trying to fetch web pages and index them.</p>
  
  <p>I would like to know when the web page was produced or about. </p>
  
  <p>For example, a news page for a date normally was created on that day around.</p>
  
  <p>How can I accurately obtain the date?</p>
  
  <p>One naive idea is to obtain the date from the HTML. Normally a news or blog page will somewhere write the date. But since HTML does not have a specific tag for it, how can I get it?</p>
  
  <p>try out different possible date format? </p>
  
  <p>Anyone can give me some suggestions? or is there any library I can use?</p>
  
  <p>Thanks</p>