ʱ : JavaJAVA程序设计 答案 - 百度文库ϿʼĶ
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(); } } }
Ŀ ѧϢϵͳͼνӦã һ һ һ
1setVisible 2Graphics User Interface 3add ѡ
1C 2C 3B 4D
1Windows±±ĴںͲ˵ 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(\ҵļ±\
// **********Ӳ˵********** fileMenu = new JMenu(\ļ\ editMenu = new JMenu(\༭\ formatMenu = new JMenu(\ʽ\
newfileItem = new JMenuItem(\½\ openfileItem = new JMenuItem(\\ savefileItem = new JMenuItem(\\ saveasfileItem = new JMenuItem(\Ϊ\ exitItem = new JMenuItem(\˳\ cutItem = new JMenuItem(\\ copyItem = new JMenuItem(\\ pasteItem = new JMenuItem(\ճ\ deleteItem = new JMenuItem(\ɾ\ findItem = new JMenuItem(\\ replaceItem = new JMenuItem(\滻\ selectallItem = new JMenuItem(\ȫѡ\
linewrapItem = new JCheckBoxMenuItem(\Զ\ fontItem = new JMenuItem(\\ 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); // ݲ˵
popMain = new JPopupMenu(); popMain.add(cutItem);
popMain.add(copyItem); popMain.add(pasteItem); popMain.add(deleteItem);
// **********Ӷı********** JScrollPane jsp = new JScrollPane(ta); add(jsp);
// **********رմʱ**********
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) { System.exit(0); } });
setExtendedState(JFrame.MAXIMIZED_BOTH); // 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鿴JDKĵ˽javax.swing.JRadioButtonMenuItemjavax.swing.JCheck BoxMenuItemֲ˵÷дԳ
¼ һ
1addActionListener 2ActionListener actionPerformed 3setEnabled
4tf.setEditable(false) 5tf.getText() ѡ
1B 2C 3C 4B 5B
1һͼνIJϷ 𰸣
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(\һ1-100֮\b2 = new JButton(\ȷ\
public Win1() {
super(\Ϸ\
setLayout(new FlowLayout()); add(b1);
add(new JLabel(\IJ²ǣ\ 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(\´ˣ\ } else if (guss < number) { mess.setText(\Сˣ\ } else {
mess.setText(\¶ˣ\ }