文章标题

package com.hxzy.string;

import java.util.Scanner;

/登录验证通过后，显示批发商品信息; 输入批发商品编号和数量，以指定格式显示总金额/

public class Demo11 {

public static void main(String[] args) {

Scanner input = new Scanner(System.in);

user1 p1 = new user1();//新建对象
boolean flag;  //定义个开关
do {
System.out.print("请输入用户名：");
String name = input.next();
System.out.print("请输入密码：");
String pwd = input.next();
flag = p1.show(name, pwd);//调用方法
} while (flag);

System.out.println("********欢迎进入商品批发城********");
System.out.println("\t编号" + "\t商品" + "\t价格");
System.out.println("\t1" + "\t电风扇" + "\t124.23");
System.out.println("\t2" + "\t洗衣机" + "\t4,500.0");
System.out.println("\t3" + "\t电视机" + "\t8,800.9");
System.out.println("\t4" + "\t冰箱" + "\t5,000.8");
System.out.println("\t5" + "\t空调" + "\t4,456.0");
System.out.println("*********************************");

System.out.print("请输入商品编号：");
int num1 = input.nextInt();
System.out.print("请输入批发数量：");
int num2 = input.nextInt();

//将整形转化成字符串

String st1 = String.valueOf(p1.showprice(num1, num2));

//将String转化成StringBuffer

StringBuffer sb = new StringBuffer(st1);

//找到 . 的位置隔3个位置给个 ， 号

for (int i = sb.indexOf(“.”) - 3; i > 0; i = i - 3) {

sb.insert(i, “,”);

}

System.out.print(“你需要付款：” + sb + “元”);

}

}

class user1 {

public boolean show(String name, String pwd) {
boolean flag = false;
if (name.equals("TOM") && pwd.equals("123")) {
System.out.println("登陆成功");
} else {
System.out.println("用户名或密码错误");
flag = true;
}
return flag;
}

// int num1 表示商品编号
// int num2 表示批发数量

public double showprice(int num1, int num2) {
double money = 0.0;

switch (num1) {
case 1:
money = (num2 * 124.23);
break;
case 2:
money = (num2 * 4500.0);
break;
case 3:
money = (num2 * 8800.9);
break;
case 4:
money = (num2 * 5000.88);
break;
case 5:
money = (num2 * 4456.0);
break;
default:
System.out.println("你输入的商品编号不存在");

}

return money;

}

}