title: threw an exception of type 'System.Data.StrongTypingException' C#
body: <pre><code>if ((booking.BookingsVoucher[i].RedemptionReloc != null)). 
  </code></pre>
  
  <p>I am getting  exception here. RedemptionReloc has null value in dbase</p>
  
  <pre><code>Redemption TimeSttmp 
  NULL 
  Redemption Reloc 
  NULL 
  RedeemedCurrencyC 
  NULL 
  Redeemed Amo_ 
  NULL 
  </code></pre>
  
  <p>tried using DBNULL.value.equal(booking.BookingsVoucher[i].RedemptionReloc). But this also throw the excepetion.
  Here is the exception log </p>
  
  <blockquote>
    <p>Exception in adding Voucher Details: System.Data.StrongTypingException: The value for column 'RedemptionReloc' in table 'BookingsVoucher' is DBNull. ---> System.InvalidCastException: Unable to cast object of type 'System.DBNull' to type 'System.String'.</p>
  </blockquote>