title: PHP Timezone Conversion from "IST GMT+5:30" to something like Asia/Kolkata
body: <p>I'm having one string like "IST GMT+5:30" and I want to convert it into something like 'Asia/Kolkata' or any Indian Time Zone.</p>
  
  <p>What I was trying is </p>
  
  <pre><code>$userSubmittedTimezoneString='IST';
  $userTimezone = new DateTimeZone($userSubmittedTimezoneString);
  print_r($userTimezone);
  </code></pre>
  
  <p>When  $userSubmittedTimezoneString='IST', it gives following output :</p>
  
  <pre><code>DateTimeZone Object ( [timezone_type] =&gt; 3 [timezone] =&gt; Asia/Jerusalem )
  </code></pre>
  
  <p>'Asia/Jerusalem' is a <strong>Israel Time Zone</strong> but what i want is <strong>India Standard Time</strong>.</p>
  
  <p>Please help me to achieve this using php.</p>
  
  <p><strong>EDIT :</strong></p>
  
  <p>"IST GMT+5:30" is dynamic. It comes from database.</p>