private void btnMonitorCacheItem_Click(object sender, EventArgs e) { string key = txtMonitorItem.Text.Trim(); if (myCache == null) { UpdateStatus("First click Connect To Cache"); return; } if (key.Length < 1) { MessageBox.Show("You must enter at least 1 valid key to montior."); return; } try { DataCacheNotificationDescriptor dcnd = myCache.AddItemLevelCallback(key, DataCacheOperations.AddItem | DataCacheOperations.RemoveItem | DataCacheOperations.ReplaceItem, DataCacheItemCallBackHandler); callbacks.Add(dcnd); //lstboxMontiorItemHistory.Items.Add("Time: " + DateTime.Now.ToLongTimeString() + " Key: " + key + " has been added to monitor list"); rtbMontiorCache.AppendText("\r" + "Time: " + DateTime.Now.ToLongTimeString() + " Key: " + key + " has been added to monitor list"); UpdateStatus("Setup ItemLevelCallBack for Item."); } catch (Exception ex) { HandleException(ex); } }