title: Ensure AM / PM (Period) does not appear in NSDateFormat stringFromDate
body: <p>The Unicode Date Format Patterns guide (<a href="http://www.unicode.org/reports/tr35/tr35-19.html#Date_Format_Patterns">here</a>) state that appending an 'a' to the format will get the period (AM or PM for instance), e.g.,</p>
  
  <pre><code>[formatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss a"];
  </code></pre>
  
  <p>However I wish to ensure that the period information does not appear but I cannot find a format string to do that. The format string I am using is as follows:</p>
  
  <pre><code>[formatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss"];
  </code></pre>
  
  <p>unfortunately, when I use stringFromDate I get the following:</p>
  
  <p><strong>2013-01-09T11:11:00 AM</strong></p>
  
  <p>I dont wish to simply strip AM or PM from the resultant string because the period syntax may be different in differing Calendars etc, I just want to stop the period information appearing.</p>
  
  <p>----8&lt;------</p>
  
  <p>Consider the following code</p>
  
  <pre><code>NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
  [formatter setLocale:[NSLocale currentLocale]];
  [formatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
  [formatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss"];
  NSString *stringDate = [formatter stringFromDate:[NSDate date]];
  
  self.labelOutput.text = stringDate;
  
  [formatter release];
  </code></pre>
  
  <p>This code will produce a string in the format I want - however I cannot use it for memory management reasons. The app I am working on is plagued by NSDateFormatter memory leaks. So we use a singleton class to provide a set number NSDateFormatters to the app which are never released and therefore we minimise how much memory is being leaked. Unfortunately these static NSDateFormatters are appending AM / PM even when I apply a date format string thus:</p>
  
  <pre><code>NSDateFormatter *formatter = [MyDateFormatter dateFormat:kFormatDateMediumStyleTimeShortStyle];
  
  [formatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
  [formatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss"];
  </code></pre>