日期:2014-05-16 浏览次数:20529 次
package bean; public class CalculatorBean { private double firstNum; private double secondNum; private char operator='+'; private double result; public double getFirstNum() { return firstNum; } public void setFirstNum(double firstNum) { this.firstNum = firstNum; } public double getSecondNum() { return secondNum; } public void setSecondNum(double secondNum) { this.secondNum = secondNum; } public char getOperator() { return operator; } public void setOperator(char operator) { this.operator = operator; } public double getResult() { return result; } public void setResult(double result) { this.result = result; } public void calculate(){ switch(this.operator){ case'+':{ this.result=this.firstNum+this.secondNum; break; } case'-':{ this.result=this.firstNum-this.secondNum; break; } case'*':{ this.result=this.firstNum*this.secondNum; break; } case'/':{ if(this.secondNum==0) { throw new RuntimeException("被除数不能为0!"); } this.result=this.firstNum/this.secondNum; break; } default: throw new RuntimeException("对不起,输入的运算符非法!"); } } }
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> </head> <body> <jsp:useBean id="CalculatorBean" class="bean.CalculatorBean"> </jsp:useBean> <jsp:setProperty name="CalculatorBean" property="*" /> <% CalculatorBean.calculate(); %> <br /> <hr> <br /> 计算的结果是: <jsp:getProperty name="CalculatorBean" property="firstNum" /> <jsp:getProperty name="CalculatorBean" property="operator" /> <jsp:getProperty name="CalculatorBean" property="secondNum" /> = <jsp:getProperty name="CalculatorBean" property="result" /> <br /> <hr> <br /> <form action="/calculator/index.jsp" method="post" style="text-align: center"> <table border="1" width="50%"> <tr style="text-align: center"> <td colspan="2">简单计算器</td> <td></td> </tr> <tr> <td>第一个参数</td> <td><input type="text" name="firstNum"> </td> </tr> <tr> <td>运算符</td> <td><select name="operator"> <option value="+">+</option> <option value="-">-</option> <option value="*">*</option> <option value="/">/</option> </select></td> </tr> <tr> <td>第二个参数</td> <td><input type="text" name="secondNum"> </td> </tr> <tr> <td colspan="2"><input type="submit" value="计 算"> </td> </tr> </table> </form> </body> </html>