protected virtual void OnFileSendBuffer(FileSendBufferEventArgs e)
 {
     if (FileSendBuffer != null)
     {
         FileSendBuffer(this, e);
     }
 }
 private void FileSendBuffer(object sender, FileSendBufferEventArgs e)
 {
     FileTransfersItem item =e.SendFileManager.Tag as FileTransfersItem;
     if (item != null)
     {
         BeginInvoke(new MethodInvoker(delegate()
         {
             item.TotalTransfersSize += e.Size;
         }));
     }
 }