private void TriggerEvent(string fileName, VerifyResult result, CompletedHandle callback = null)
 {
     if (callback != null)
     {
         try
         {
             callback(this, result);
         }
         catch (Exception exp)
         {
             Logger.AddLog(this.GetType(), "TriggerEvent", exp.Message);
         }
     }
     else if (OnCompleted != null)
     {
         try
         {
             OnCompleted(this, result);
         }
         catch (Exception exp)
         {
             Logger.AddLog(this.GetType(), "TriggerEvent", exp.Message);
         }
     }
 }
 public void VerifyPersonAsync(string url, string fileName, Image alarmImg, Dictionary <string, string> formItems = null, CompletedHandle callback = null)
 {
     ThreadPool.QueueUserWorkItem(delegate
     {
         VerifyResult result = VerifyImage(url, fileName, alarmImg, formItems);
         TriggerEvent(fileName, result, callback);
     });
 }