使用JAVA 编写一个程序，显示5中商品价格，用户可以选择多种商品并在其后的文本框输入购买的数量。 100
用java Swing做的？给你个代码，还有运行结果图
package my.test.main;
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.EmptyBorder;
import javax.swing.event.AncestorEvent;
import javax.swing.event.AncestorListener;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
import javax.swing.JLabel;
import javax.swing.JTextField;
public class Purchase extends JFrame {
private JPanel contentPane;
private JTextField textField;
private JTextField textField_1;
private JTextField textField_2;
private JTextField textField_3;
private JTextField textField_4;
private JLabel label_9;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Purchase frame = new Purchase();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public Purchase() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
JLabel label = new JLabel("\u5546\u54C11");
label.setBounds(56, 40, 54, 15);
contentPane.add(label);
JLabel label_1 = new JLabel("\u5546\u54C12");
label_1.setBounds(56, 70, 54, 15);
contentPane.add(label_1);
JLabel label_2 = new JLabel("\u5546\u54C13");
label_2.setBounds(56, 100, 54, 15);
contentPane.add(label_2);
JLabel label_3 = new JLabel("\u5546\u54C14");
label_3.setBounds(56, 130, 54, 15);
contentPane.add(label_3);
JLabel label_4 = new JLabel("\u5546\u54C15");
label_4.setBounds(56, 160, 54, 15);
contentPane.add(label_4);
JLabel label_5 = new JLabel("\u5546\u54C1\u540D\u79F0");
label_5.setBounds(56, 7, 54, 15);
contentPane.add(label_5);
JLabel label_6 = new JLabel("单价");
label_6.setBounds(179, 7, 54, 15);
contentPane.add(label_6);
JLabel label_7 = new JLabel("数量");
label_7.setBounds(307, 7, 54, 15);
contentPane.add(label_7);
JLabel label_8 = new JLabel("总价");
label_8.setBounds(145, 224, 54, 15);
contentPane.add(label_8);
label_9 = new JLabel("0");
label_9.setBounds(209, 224, 54, 15);
contentPane.add(label_9);
JLabel label_10 = new JLabel("10");
label_10.setBounds(185, 40, 54, 15);
contentPane.add(label_10);
JLabel label_11 = new JLabel("20");
label_11.setBounds(185, 70, 54, 15);
contentPane.add(label_11);
JLabel label_12 = new JLabel("30");
label_12.setBounds(185, 100, 54, 15);
contentPane.add(label_12);
JLabel label_13 = new JLabel("40");
label_13.setBounds(185, 130, 54, 15);
contentPane.add(label_13);
JLabel label_14 = new JLabel("50");
label_14.setBounds(185, 160, 54, 15);
contentPane.add(label_14);
textField = new JTextField();
textField.setBounds(295, 37, 66, 21);
contentPane.add(textField);
textField.setColumns(10);
textField.addKeyListener(new CalcTotle());
textField_1 = new JTextField();
textField_1.setColumns(10);
textField_1.setBounds(295, 67, 66, 21);
contentPane.add(textField_1);
textField_1.addKeyListener(new CalcTotle());
textField_2 = new JTextField();
textField_2.setColumns(10);
textField_2.setBounds(295, 97, 66, 21);
contentPane.add(textField_2);
textField_2.addKeyListener(new CalcTotle());
textField_3 = new JTextField();
textField_3.setColumns(10);
textField_3.setBounds(295, 127, 66, 21);
contentPane.add(textField_3);
textField_3.addKeyListener(new CalcTotle());
textField_4 = new JTextField();
textField_4.setColumns(10);
textField_4.setBounds(295, 157, 66, 21);
contentPane.add(textField_4);
textField_4.addKeyListener(new CalcTotle());
}
class CalcTotle extends KeyAdapter {
@Override
public void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub
int count1, count2, count3, count4, count5;
if (!textField.getText().isEmpty()) {
count1 = Integer.parseInt(textField.getText()) * 10;
} else {
count1 = 0;
}
if (!textField_1.getText().isEmpty()) {
count2 = Integer.parseInt(textField_1.getText()) * 20;
} else {
count2 = 0;
}
if (!textField_2.getText().isEmpty()) {
count3 = Integer.parseInt(textField_2.getText()) * 30;
} else {
count3 = 0;
}
if (!textField_3.getText().isEmpty()) {
count4 = Integer.parseInt(textField_3.getText()) * 40;
} else {
count4 = 0;
}
if (!textField_4.getText().isEmpty()) {
count5 = Integer.parseInt(textField_4.getText()) * 50;
} else {
count5 = 0;
}
final int totle = count1 + count2 + count3 + count4 + count5;
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
// TODO Auto-generated method stub
label_9.setText(totle + "");
}
});
}
}
}
有错误大神，指点一下我是自学
听你的意思，有文本框输入，像是html的东西，不是java，代码如下，效果图，
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<script type="text/javascript">
function a(){
var a = document.getElementById("apple").value;
document.getElementById("a").innerText=a*5;
}
function b(){
var b = document.getElementById("banana").value;
document.getElementById("b").innerText=b*6;
}
function o(){
var o = document.getElementById("orange").value;
document.getElementById("o").innerText=o*7;
}
function p(){
var p = document.getElementById("potato").value;
document.getElementById("p").innerText=p*8;
}
function f(){
var f = document.getElementById("fish").value;
document.getElementById("f").innerText=f*20;
}
</script>
<body onload="a(),b(),o(),p(),f()">
苹果 :<span>单价：5元</span><input type="text" name="apple" id="apple" onblur="a()" value="1"/><span id="a"></span><br><br>
香蕉 :<span>单价：6元</span><input type="text" name="banana" id="banana" onblur="b()" value="1"/><span id="b"></span><br><br>
橙子 :<span>单价：7元</span><input type="text" name="orange" id="orange" onblur="o()" value="1"/><span id="o"></span><br><br>
西红柿:<span>单价：8元</span><input type="text" name="potato" id="potato" onblur="p()" value="1"/><span id="p"></span><br><br>
鱼 :<span>单价：20元</span><input type="text" name="fish" id="fish" onblur="f()" value="1"/><span id="f"></span><br><br>
</body>
</html>
使用switch方法
int num=0,1,2,3;
switch(num){
case 0:{System.out.println("num=0");}
case 1:{System.out.println("num=1");}
case 2:{System.out.println("num=2");}
case 3:{System.out.println("num=3");}
break;
}
