![](https://static.youtibao.com/asksite/comm/h5/images/m_q_title.png)
[单选题]
vi处于命令状态时,按下下列哪组按键可以把正在编辑的内容保存到磁盘上?()
A.zz
B.:wq回车
C.Ctrl-S
D.Ctrl-G
查看答案
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)
A.zz
B.:wq回车
C.Ctrl-S
D.Ctrl-G
下面ChangeTitle()中对b1和b2按键构造监听器,实现当按下b1键时标题变为Students,当按下b2键时标题变为Teachers。添加空缺的语句。 ... public ChangeTitle() { super("Title Bar"); b1.addActionListener(this); 【 】; Jpanel pane = new Jpane1(); Pane.add(b1); Pane.add(b2); SetContentPane(pane); } public void actionPerformed(ActionEvent evt) { Object sourve = evt.getSource(); if (sourve ==b1) setTitle("Students"); else if (source == b2) setTitle("Teachers"); repaint(); } ...
A.过滤器处于“自动”模式工作;
B.设备处于运行状态;
C.反洗泵、絮凝剂泵、氧化剂泵在自动工作模式;
D.反洗水箱液位高于1.20米;