大家帮我看看,错在那里了

[miaomiao3571]

import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class AppletInteger1 extends Applet implements
ActionListener{
Label inputLB;
TextField input;
int ing;
Integer outIng;
String str1,str2,str3;
public void init(){
intputLB=new Label("請輸入一個數字字符串");
intput=new TextField(5);
add(inputLB);
add(input);
input.addActionListener(this);
}
public void paint(Graphics g)
{
g.drawString("二進紙表示: "+str1,100,100);
g.drawString("十六進紙表示: "+str2,100,150);
g.drawString("八進紙表示: "+str3,100,200);
}
public void actionperformed(ActionEvent e)
{
ing=Integer.valueOf(input.getText()).intValue();
outIng=new Integer(ing);
str1=outIng.toBinaryString(ing);
str2=outIng.toHexString(ing);
str3=outIng.toOctalString(ing);
repaint();
}
}

[miaomiao3571]

为什么要覆盖actionPerformed(java.awt.event.ActionEvent),这是什么意思啊?

[runshine]

因为你没覆盖
actionPerformed(java.awt.event.ActionEvent)

intputLB你在前面定义的是inputLB

修改后

import   java.awt.*; 
import   java.awt.event.*; 
import   java.applet.*; 

public   class   AppletInteger1   extends   Applet   implements 
      ActionListener{ 
      //public void actionPerformed(java.awt.event.ActionEvent e){}
              Label   inputLB; 
              TextField   input; 
              int   ing; 
              Integer   outIng; 
              String   str1,str2,str3; 
    public   void   init(){ 
                intputLB=new   Label("請輸入一個數字字符串"); 
                input=new   TextField(5); 
                add(inputLB); 
                add(input); 
                input.addActionListener(this); 
                                        } 
      public   void   paint(Graphics   g) 
{ 
  g.drawString("二進紙表示:   "+str1,100,100); 
  g.drawString("十六進紙表示:   "+str2,100,150); 
  g.drawString("八進紙表示:   "+str3,100,200); 
} 
public   void   actionperformed(ActionEvent   e) 
{ 
  ing=Integer.valueOf(input.getText()).intValue(); 
  outIng=new   Integer(ing); 
str1=outIng.toBinaryString(ing); 
str2=outIng.toHexString(ing); 
str3=outIng.toOctalString(ing); 
repaint(); 
} 
                                    

}

具体main方法怎么写就看你自己了。

[seaforce]

注意函数的大小写，，你就是名都写错了
－－－－－－－－－－－－－－－－－－－－

/**
 * project_name: Test
 * package_name: csdn_Test_20071126
 * package_declaration: package csdn_Test_20071126;
 * filename: AppletInteger1.java
 * author: yuhaiming
 * date: 2007-12-11
 */
package csdn_Test_20071126;

import   java.awt.*; 
import   java.awt.event.*; 
import   java.applet.*; 

public   class   AppletInteger   extends   Applet   implements 
      ActionListener{ 
              Label   inputLB; 
              TextField   input; 
              int   ing; 
              Integer   outIng; 
              String   str1,str2,str3; 
    public   void   init(){ 
    	inputLB=new   Label("請輸入一個數字字符串"); 
    	input=new   TextField(5); 
                add(inputLB); 
                add(input); 
                input.addActionListener(this); 
    } 
    
    public   void   paint(Graphics   g) { 
		  g.drawString("二進紙表示:   "+str1,100,100); 
		  g.drawString("十六進紙表示:   "+str2,100,150); 
		  g.drawString("八進紙表示:   "+str3,100,200); 
	} 
	public   void   actionPerformed(ActionEvent   e) 
	{ 
		ing=Integer.valueOf(input.getText()).intValue(); 
		outIng=new   Integer(ing); 
		str1=outIng.toBinaryString(ing); 
		str2=outIng.toHexString(ing); 
		str3=outIng.toOctalString(ing); 
		repaint(); 
	} 
                                   
}

[runshine]

覆盖的
actionPerformed(java.awt.event.ActionEvent)
方法被我注释掉了，里面要添加什么你自己凭需要吧。什么都不需要，解开注释就可以了。