Question

Java中怎样通过界面操作读取任何一个文件夹里的文件

Answer 1

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.io.File;

import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.WindowConstants;

public class Demo extends javax.swing.JFrame {
private JPanel jPanel1;

private JTextArea jTextArea1;

private JScrollPane jScrollPane1;

private JButton jButton1;

private JTextField jTextField1;

public static void main(String[] args) {

Demo inst = new Demo();
inst.setLocationRelativeTo(null);
inst.setVisible(true);

}

public Demo() {
super();
initGUI();
}

private void initGUI() {
try {
setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
{
jPanel1 = new JPanel();
getContentPane().add(jPanel1, BorderLayout.CENTER);
jPanel1.setLayout(null);
{
jTextField1 = new JTextField();
jPanel1.add(jTextField1);
jTextField1.setText("请输入您要读取的文件夹的路径");
jTextField1.addFocusListener(new FocusAdapter() {
@Override
public void focusGained(FocusEvent e) {
jTextField1.setText("");
}
});
jTextField1.setBounds(16, 18, 174, 22);
}
{
jButton1 = new JButton();
jPanel1.add(jButton1);
jButton1.setText("读取");
jButton1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
File path = new File(jTextField1.getText());
String files[] = path.list();
for (int i = 0; i < files.length; i++) {
jTextArea1.append(files[i] + "\n");
}

}
});
jButton1.setBounds(238, 15, 81, 28);
}
{
jScrollPane1 = new JScrollPane();
jPanel1.add(jScrollPane1);
jScrollPane1.setBounds(12, 65, 368, 188);
{
jTextArea1 = new JTextArea();
jScrollPane1.setViewportView(jTextArea1);
jTextArea1.setText("");
}
}
}
this.getRootPane().setDefaultButton(jButton1);
pack();
setSize(400, 300);
} catch (Exception e) {
e.printStackTrace();
}
}

}

Answer 2

import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.TextArea;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import javax.swing.JButton;
import javax.swing.JFrame;
public class GUIDemo1 extends JFrame{
private static final String TARGET_FILE = "F:\\a.txt";
private JButton saveButton;
private JButton loadButton;
private TextArea textArea;
private Container container;
private File targetFile;
public GUIDemo1() throws IOException {
super("File Demo");
setLayout(new FlowLayout());
container = getContentPane();
targetFile = new File(TARGET_FILE);
if(targetFile.createNewFile()) {
System.out.println("文件不存在，创建成功");
}else {
System.out.println("文件存在");
}
textArea = new TextArea();
saveButton = new JButton("save");
loadButton = new JButton("load");
saveButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
try {
FileWriter writer = new FileWriter(targetFile);
String result = textArea.getText();
writer.write(result);
writer.close();
textArea.setText("");
System.out.println("存档成功");
} catch (IOException e1) {
e1.printStackTrace();
}
}
});
loadButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
try {
FileReader reader = new FileReader(targetFile);
char[] buffer = new char[1024];
StringBuffer result = new StringBuffer();
int len;
while((len = reader.read(buffer)) != -1) {
result.append(buffer,0,len);
}
reader.close();
textArea.setText(result.toString());
System.out.println("读档成功");
} catch (FileNotFoundException e1) {
e1.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
}
}
});
container.add(textArea);
container.add(loadButton);
container.add(saveButton);
setSize(500, 300);
setVisible(true);
}
public static void main(String[] args) throws IOException {
GUIDemo1 demo = new GUIDemo1();
demo.setDefaultCloseOperation(EXIT_ON_CLOSE);
}
}