一个JAVA 字符替换的问题
public class myapplet extends Appletimplements ActionListener
{
TextArea area;
Label ccc;
TextField name1,name2;
Button btn;
String c1,c2,c3;
public void init()
{
name1=new TextField(8);
ccc=new Label("替换成");
name2=new TextField(8);
btn=new Button("确定");
area=new TextArea(4,20);
add(name1);
add(ccc);
add(name2);
add(btn);
add(area);
btn.addActionListener(this);
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==btn)
c1=name2.getText();
c2=name1.getText();
c3=new String(area.getText());
System.out.println(area.setText(c3.replace(c1,c2)));
}
}
为什么运行后 告诉我 Sytem.out.println(area.steText(c3.replace(c1,c2)));
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