使用JFileChooser打开文件

作为一个小小的项目，我认为制作文本编辑器会很酷。 我目前仍然坚持打开文件。 这是我打开文件的代码（ e是一个ActionEvent ，open是一个JMenuItem ）：

 else if (e.getSource() == open) { JFileChooser choice = new JFileChooser(); int option = choice.showOpenDialog(this); if (option == JFileChooser.APPROVE_OPTION) { try{ Scanner scan = new Scanner(new FileReader((open).getSelectedFile().getPath())); } } } 

try块给了我麻烦。 Eclipse表示getSelectedFile()未定义类型JMenuItem 。 对于MenuItem它似乎也是未定义的。 有没有其他方法可以解决这个问题，还是另一种方法可以解决这个问题？

Answer 1

一旦返回，您需要在JFileChooser上调用getSelectedFile() ，因此请将代码更改为：

 choice.getSelectedFile() 

Answer 2

  private void selectfileActionPerformed(java.awt.event.ActionEvent evt) { JFileChooser jFileChooser=new JFileChooser(); StringBuffer buffer; buffer = new StringBuffer(); int result= jFileChooser.showOpenDialog(this); if(result==JFileChooser.APPROVE_OPTION) { try { FileReader reader; reader = null; JOptionPane.showMessageDialog(this,"hii user clicked open sysytem"); File file=jFileChooser.getSelectedFile(); reader=new FileReader(file); int i=1; while(i!=-1) { i=reader.read(); char ch=(char) i; buffer.append(ch); } notepad.setText(buffer.toString()); } catch (FileNotFoundException ex) { Logger.getLogger(MainForm.class.getName()).log(Level.SEVERE, null, ex); } catch (IOException ex) { Logger.getLogger(MainForm.class.getName()).log(Level.SEVERE, null, ex); } } } 

Answer 3

 import java.awt.EventQueue; public class FileChooser extends JFrame { private JPanel contentPane; String filename; // main public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { FileChooser frame = new FileChooser(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } public FileChooser() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 450, 300); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); setContentPane(contentPane); contentPane.setLayout(null); // button to selct file JButton btnNewButton = new JButton("Select file"); btnNewButton.setBounds(10, 2, 89, 23); contentPane.add(btnNewButton); // area to display file content final JTextArea textArea = new JTextArea(); textArea.setBounds(10, 36, 414, 215); contentPane.add(textArea); // save button final JButton btnSave = new JButton("Save"); btnSave.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent arg0) { try { FileWriter writer = new FileWriter(filename.replace(".", "_out.")); BufferedWriter bwr = new BufferedWriter(writer); bwr.write(textArea.getText()); bwr.close(); writer.close(); System.out.println(textArea.getText()); } catch (Exception e) { System.out.println("Error"); } } }); btnSave.setBounds(283, 2, 89, 23); contentPane.add(btnSave); // listen to button clicks btnNewButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent ae) { JFileChooser fileChooser = new JFileChooser(); int returnValue = fileChooser.showOpenDialog(null); if (returnValue == JFileChooser.APPROVE_OPTION) { File selectedFile = fileChooser.getSelectedFile(); filename = selectedFile.getAbsolutePath(); try { FileReader reader = new FileReader(filename); BufferedReader br = new BufferedReader(reader); textArea.read(br, null); br.close(); System.out.println(textArea.getText()); } catch (Exception e) { System.out.println("Error"); }enter code here } } enter code here }); } }