title: Set dbtype to null or Int for SQL output parameter
body: <p>I am returning registrationID as an output of the store procedure. Store procedure can return null or int value.So I am writing following code in my C#.I want to set up dbtype null or int then how can I do that.</p>
  
  <pre><code> p.Add("@TotalRebate", bk.TotalRebate);
   p.Add("@PromotionId", bk.PromotionId);
   p.Add("@RegistrationId", bk.RegistrationId, dbType: DbType.Int32, direction: ParameterDirection.Output);
   _db.Execute("InsertBookingNo", p, commandType: CommandType.StoredProcedure);
  
      var registrationId = p.Get&lt;int&gt;("@RegistrationId");
  </code></pre>
  
  <p>Thanks</p>