Question

在JAVA中 如何将一个文本框中的内容取出 并保存在一个文件之中

还有将一个文件的内容读入到一个文本框中 JAVA

Answer 1

import java.io.*;
import javax.swing.*;
import java.awt.FlowLayout;
import java.awt.event.*;
public class WriterTo extends JFrame implements ActionListener{
JButton b;JTextField t;
public WriterTo(){
super("文本框内容写入文件");
JLabel l=new JLabel("请输入内容：");
t=new JTextField(20);
b=new JButton("写入");
b.addActionListener(this);
this.add(l);
this.add(t);
this.add(b);
this.setLayout(new FlowLayout());
this.pack();
this.setVisible(true);
}
public void actionPerformed(ActionEvent e) {
if(e.getSource()==b){
if(t.getText().equals("")){
JOptionPane.showMessageDialog(null,"请输入内容~","错误",JOptionPane.ERROR_MESSAGE);
t.grabFocus();
}else{
write(t.getText());
JOptionPane.showMessageDialog(null,"写入成功","提示",JOptionPane.INFORMATION_MESSAGE);
}
}
}
public void write(String line){
try{
File f=new File("c:/文本框.txt");//向指定文本框内写入
FileWriter fw=new FileWriter(f);
fw.write(line);
fw.close();
}catch(Exception e){

}
}
public static void main(String[] args) {
new WriterTo();
}

}

Answer 2

用输入输出流