解决方案
以下示例演示了如何通过使用 TextArea() 制作标签在浏览器中写入 textarea 然后使用 File() 构造函数创建文件来写入文件。
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.applet.Applet;
import java.net.*;
public class WriteFile extends Applet {
Button write = new Button("WriteToFile");
Label label1 = new Label("Enter the file name:");
TextField text = new TextField(20);
Label label2 = new Label("Write your text:");
TextArea area = new TextArea(10,20);
public void init() {
add(label1);
label1.setBackground(Color.lightGray);
add(text);
add(label2);
label2.setBackground(Color.lightGray);
add(area);
add(write,BorderLayout.CENTER);
write.addActionListener(new ActionListener () {
public void actionPerformed(ActionEvent e) {
new WriteText();
}
});
}
public class WriteText {
WriteText() {
try {
String str = text.getText();
if(str.equals("")) {
JOptionPane.showMessageDialog(null, "Please enter the file name!");
text.requestFocus();
} else {
File f = new File(str);
if(f.exists()) {
BufferedWriter out = new BufferedWriter(new FileWriter(f,true));
if(area.getText().equals("")) {
JOptionPane.showMessageDialog (null,"Please enter your text!");
area.requestFocus();
} else {
out.write(area.getText());
if(f.canWrite()) {
JOptionPane.showMessageDialog(null, "Text is written in "+str);
text.setText("");
area.setText("");
text.requestFocus();
} else {
JOptionPane.showMessageDialog(null, "Text isn't written in "+str);
}
out.close();
}
} else {
JOptionPane.showMessageDialog (null,"File not found!");
text.setText("");
text.requestFocus();
}
}
} catch(Exception x) {
x.printStackTrace();
}
}
}
}
