怎样实现“查找”功能。(一定给分！)

Question

具体不大清楚，好象先建立一个模式，当然模式中包含要匹配的字符串，之后调用
该模式的match方法，该方法有一个参数就是你的计事本中的字符串。

Answer 1

利用java string 的 indexOf 方法，等于-1是不存在了！

Answer 2

找段网上的例子，供你参考：    else if(ae.getSource() == menuEditFind) {
      JDialog ds = new JDialog(this, "Find", true);
      ds.getContentPane().setLayout(new FlowLayout());
      ds.setResizable(false);
      final JLabel dsMessage1 = new JLabel("   Found counts:  ");
      final JLabel dsMessage2 = new JLabel(" 0");
      final Checkbox dsLoop = new Checkbox("Loop   ");
      dsLoop.setState(findingLoop);
      final Checkbox dsMatchCase = new Checkbox("Match Case  ");
      final TextField tfs = new TextField(15);
      ds.getContentPane().add(tfs);
      tfs.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
          int a = 0, b = 0;
          String str1, str2, str3, str4, strA, strB;
          str1 = ta.getText();
          str2 = str1.toLowerCase();
          str3 = tfs.getText();
          str4 = str3.toLowerCase();
          if(dsMatchCase.getState()) {
            strA = str1;
            strB = str3;
          }
          else {
            strA = str2;
            strB = str4;
          }
          a = strA.indexOf(strB, FindStartPos);
          if(a > -1) {
            ta.setCaretPosition(a);
            b = tfs.getText().length();
            ta.select(a, a + b);
            FindStartPos = a + b;
            foundCount++;
            dsMessage2.setText(foundCount + "");
          }
          else {
            if(dsLoop.getState()) {
              JOptionPane.showMessageDialog(null, "End of file.", "Find result", JOptionPane.INFORMATION_MESSAGE);
              FindStartPos = 0;
            }
            else {
              JOptionPane.showMessageDialog(null, "End of file.", "Find result", JOptionPane.INFORMATION_MESSAGE);
            }
            foundCount = 0;
          }
        }
      });
      Button bs = new Button("   Find  ");
      //same as tfs.addActionListener(new ActionListener() {
      bs.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
          int a = 0, b = 0;
          String str1, str2, str3, str4, strA, strB;
          str1 = ta.getText();
          str2 = str1.toLowerCase();
          str3 = tfs.getText();
          str4 = str3.toLowerCase();
          if(dsMatchCase.getState()) {
            strA = str1;
            strB = str3;
          }
          else {
            strA = str2;
            strB = str4;
          }
          a = strA.indexOf(strB, FindStartPos);
          if(a > -1) {
            ta.setCaretPosition(a);
            b = tfs.getText().length();
            ta.select(a, a + b);
            FindStartPos = a + b;
            foundCount++;
            dsMessage2.setText(foundCount + "");
          }
          else {
            if(dsLoop.getState()) {
              JOptionPane.showMessageDialog(null, "End of file.", "Find result", JOptionPane.INFORMATION_MESSAGE);
              FindStartPos = 0;
            }
            else {
              JOptionPane.showMessageDialog(null, "End of file.", "Find result", JOptionPane.INFORMATION_MESSAGE);
            }
            foundCount = 0;
          }
        }
      });
      Button bsc = new Button("Cancel");
      bsc.addActionListener(new ActionListener() {
                              public void actionPerformed(ActionEvent e) {
                                dispose();
                                foundCount = 0;
                              }
                           });
      ds.getContentPane().add(bs);
      ds.getContentPane().add(bsc);
      ds.getContentPane().add(dsLoop);
      ds.getContentPane().add(dsMatchCase);
      ds.getContentPane().add(dsMessage1);
      ds.getContentPane().add(dsMessage2);
      ds.setLocation(120, 120);
      ds.addWindowListener(new WindowAdapter() {
                             public void windowClosing(WindowEvent e) {
                               dispose();
                               FindStartPos = 0;
                             }
                           });
      ds.setSize(260,110);
      ds.setVisible(true);
    }