JavaJAVA绋嬪簭璁捐�� 绛旀�� - 鐧惧害鏂囧簱

File file = new File(\ String str; int n = 0; try {

fr = new FileReader(file); br = new BufferedReader(fr);

while ((str = br.readLine()) != null) { n++;

System.out.println(n + \ }

} catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } }

项目三 学生信息管理系统（图形界面设计应用） 任务一 界面设计 子任务一 主界面设计 （一）填空题

1．setVisible 2．Graphics User Interface 3．add （二）选择题

1．C 2．C 3．B 4．D （三）编程题

1．仿照Windows记事本，制作记事本的窗口和菜单。 package pr3;

import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import javax.swing.JCheckBoxMenuItem; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JPopupMenu; import javax.swing.JScrollPane; import javax.swing.JTextArea; class Myjsb extends JFrame {

JTextArea ta = new JTextArea(); JMenuBar bar = new JMenuBar();

JMenu fileMenu, editMenu, formatMenu;

JMenuItem newfileItem, openfileItem, savefileItem, saveasfileItem, exitItem, cutItem, copyItem, pasteItem, deleteItem, findItem, replaceItem, selectallItem, linewrapItem, fontItem;

JPopupMenu popMain;

public Myjsb() {

super(\我的记事本\

// **********添加菜单********** fileMenu = new JMenu(\文件\ editMenu = new JMenu(\编辑\ formatMenu = new JMenu(\格式\

newfileItem = new JMenuItem(\新建\ openfileItem = new JMenuItem(\打开\ savefileItem = new JMenuItem(\保存\ saveasfileItem = new JMenuItem(\另存为\ exitItem = new JMenuItem(\退出\ cutItem = new JMenuItem(\剪切\ copyItem = new JMenuItem(\复制\ pasteItem = new JMenuItem(\粘贴\ deleteItem = new JMenuItem(\删除\ findItem = new JMenuItem(\查找\ replaceItem = new JMenuItem(\替换\ selectallItem = new JMenuItem(\全选\

linewrapItem = new JCheckBoxMenuItem(\自动换行\ fontItem = new JMenuItem(\字体\ fileMenu.add(newfileItem); fileMenu.add(openfileItem); fileMenu.add(savefileItem); fileMenu.add(saveasfileItem); fileMenu.addSeparator(); fileMenu.add(exitItem); editMenu.add(cutItem); editMenu.add(copyItem); editMenu.add(pasteItem); editMenu.add(deleteItem); editMenu.addSeparator(); editMenu.add(findItem); editMenu.add(replaceItem); formatMenu.add(linewrapItem); formatMenu.add(fontItem); bar.add(fileMenu); bar.add(editMenu); bar.add(formatMenu); setJMenuBar(bar); // 快捷菜单

popMain = new JPopupMenu(); popMain.add(cutItem);

popMain.add(copyItem); popMain.add(pasteItem); popMain.add(deleteItem);

// **********添加多行文本框********** JScrollPane jsp = new JScrollPane(ta); add(jsp);

// **********关闭窗口时**********

addWindowListener(new WindowAdapter() {

public void windowClosing(WindowEvent e) { System.exit(0); } });

setExtendedState(JFrame.MAXIMIZED_BOTH); // 窗口最大化 setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setVisible(true); } }

public class lx3_1_1_1 {

public static void main(String[] args) { Myjsb win = new Myjsb(); } }

2．查看JDK帮助文档，了解javax.swing.JRadioButtonMenuItem和javax.swing.JCheck BoxMenuItem两种菜单项的用法，并编写测试程序。

子任务二 登录界面 （一）填空题

1．addActionListener 2．ActionListener actionPerformed 3．setEnabled

4．tf.setEditable(false) 5．tf.getText() （二）选择题

1．B 2．C 3．C 4．B 5．B （三）编程题

1．设计一个图形界面的猜数游戏程序。 答案：

package pr3;

import java.awt.Dimension; import java.awt.FlowLayout; import java.awt.Toolkit;

import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JTextField;

class Win1 extends JFrame implements ActionListener { int number;

JTextField t1 = new JTextField(10);

JLabel mess = new JLabel(\

JButton b1 = new JButton(\点击产生一个1-100之间的随机数\b2 = new JButton(\确定\

public Win1() {

super(\猜数游戏\

setLayout(new FlowLayout()); add(b1);

add(new JLabel(\你的猜测是：\ add(t1); add(b2); add(mess);

b1.addActionListener(this); b2.addActionListener(this);

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); Dimension frameSize = new Dimension(250, 130); if (frameSize.height > screenSize.height) { frameSize.height = screenSize.height; }

if (frameSize.width > screenSize.width) { frameSize.width = screenSize.width; }

setLocation(((screenSize.width - frameSize.width) / 2), ((screenSize.height - frameSize.height) / 2)); setSize(frameSize);

this.setResizable(false); this.setVisible(true); }

public void actionPerformed(ActionEvent e) { if (e.getSource() == b1) {

number = (int) (Math.random() * 100 + 1); } else if (e.getSource() == b2) { try {

int guss = Integer.parseInt(t1.getText()); if (guss > number) {

mess.setText(\猜大了！\ } else if (guss < number) { mess.setText(\猜小了！\ } else {

mess.setText(\猜对了！\ }