谁能帮我解释下这个程序,谢谢了
Ginie 2008-05-06 02:34:33 谁能帮我解释下这个程序,问题在下面,谢谢了
import java.awt.*;
import java.awt.event.*;
public class frame implements ActionListener
{
static TextField text1=new TextField();
static TextField text2=new TextField();
static TextField text3=new TextField();
static Button Btn1=new Button("加");
static Button Btn2=new Button("差");
static Button Btn3=new Button("积");
static Button Btn4=new Button("除");
public static void main(String[] args)
{
Frame f=new Frame("计算");
f.setLayout(new FlowLayout());
f.addWindowListener(new WindowAdapter()
{
public void WindowClosing(WindowEvent e)
{
System.exit(0);
}
}
);
f.add(Btn1);
f.add(Btn2);
f.add(Btn3);
f.add(Btn4);
f.add(text1);
f.add(text2);
f.add(text3);
Btn1.addActionListener(new frame());
Btn2.addActionListener(new frame());
Btn3.addActionListener(new frame());
Btn4.addActionListener(new frame());
f.setVisible(true);
}
public void actionPerformed(ActionEvent ex)
{
int T1,T2,T3;
String s1;
try{
T1=Integer.parseInt(text1.getText());
T2=Integer.parseInt(text2.getText());
if(ex.getSource()==Btn1)
{
T3=T1+T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
else if(ex.getSource()==Btn2)
{
T3=T1-T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
else if(ex.getSource()==Btn3)
{
T3=T1*T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
else if(ex.getSource()==Btn4)
{
T3=T1/T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
}catch(Exception exs){
exs.printStackTrace();
}
}
}
能告诉我为什么这里要异常处理,谢谢了
try{
T1=Integer.parseInt(text1.getText());
T2=Integer.parseInt(text2.getText());
if(ex.getSource()==Btn1)
{
T3=T1+T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
else if(ex.getSource()==Btn2)
{
T3=T1-T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
else if(ex.getSource()==Btn3)
{
T3=T1*T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
else if(ex.getSource()==Btn4)
{
T3=T1/T2;
s1=String.valueOf(T3);
text3.setText(s1);
}
}catch(Exception exs){
exs.printStackTrace();
}
还有就是为什么这里都要定义为静态的。能详细说下吗,谢谢。(^_^)