title: Regular expression in javascript to check time with date
body: <p>I need to check whether the text contains a date part with it.</p>
  
  <p>for ex: <code>mytext_12/26/2011_11:51_AM or someText_12/26/2011_13:51_PM</code> have a date part it returns true.</p>
  
  <p>I am not too good with expressions so looking for one. the format of the date - time  part is fixed.</p>
  
  <p>i got a way out for it but failing for time .</p>
  
  <pre><code>var containsDate = ~str.search(/\d{1,2}\/\d{1,2}\/\d{4}/);
  </code></pre>
  
  <p>it checks the date part perfectly but when i am trying for the time part i am messing it up some where .</p>
  
  <pre><code>_\d{1,2}:\d{2}_(?:AM|PM) this is the part for time but i am not able to generate the final regex by combining this two.
  </code></pre>