交互拾取点时 右键取消 禁止出现点无效

  PromptPointOptions prpointoptions = new PromptPointOptions("\n请选择线缆拐点");
  prpointoptions.AllowNone = true;//右键取消 禁止出现点无效
  PromptPointResult prPointRes = ed.GetPoint(prpointoptions);