e1303.java

java小程序

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class E1303 extends JFrame implements ItemListener
{
Container c;
JCheckBox uc=new JCheckBox("upperCase");
JTextArea ta=new JTextArea("JCheckBox测试",4,30);
public E1303()
{
super("E1303.java:CheckBox测试");
c=getContentPane();
c.setLayout(new FlowLayout(FlowLayout.CENTER));
c.add(uc);
c.add(ta);
uc.addItemListener(this);
setSize(400,200);
setVisible(true);
}
public void itemStateChanged(ItemEvent e)
{
if(e.getSource()==uc)
{
if(e.getStateChange()==ItemEvent.SELECTED)
{
String str=ta.getText();
//String str="JCheckBox";
char[] ca=str.toCharArray();
int l=ca.length;
for(int i=0;i<l;i++)
if((ca[i]>=97)&&(ca[i]<=122))
ca[i]-=32;
String str1=new String(ca);
ta.replaceRange(str1,0,l);
ta.repaint();
}
}
}

public static void main(String args[])
{
E1303 app=new E1303();
app.addWindowListener(new MyWindowListener());
}
}