输入两个数实现加减乘除，结果输出到页面上
简易的jsp代码，有两个输入框，四个提交按钮
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<form action="addalltwo.jsp" method="post">
number1:<input name="number1" type="text"><br>
number2:<input name="number2" type="text"><br>
<input name="in" type="submit" value="+">
<input name="in" type="submit" value="-">
<input name="in" type="submit" value="*">
<input name="in" type="submit" value="/">
</form>
</body>
</html>
嵌套在jsp中的java代码，接收两个输入值，通过判断运算符进行相应运算，注意除数不为零的情况通过<%=%>输出嵌套在jsp中的java值
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<form action="" method="post">
number1:<input name="number1" type="text"><br>
number2:<input name="number2" type="text"><br>
<input name="in" type="submit" value="+">
<input name="in" type="submit" value="-">
<input name="in" type="submit" value="*">
<input name="in" type="submit" value="/">
</form>
<%
String number1=request.getParameter("number1");
int n1= Integer.parseInt(number1);
String number2=request.getParameter("number2");
int n2=Integer.parseInt(number2);
String in=request.getParameter("in");
String result="";
if("+".equals(in)){
result= String.valueOf(n1+n2);
}
if("-".equals(in)){
result= String.valueOf(n1-n2);
}
if("*".equals(in)){
result= String.valueOf(n1*n2);
}
if("/".equals(in)){
if("0".equals(number2)){
result="除数不能为零";
}else {
result= String.valueOf(n1/n2);
}
}
%>
<p style="color: #0066FF">结果:<%=n1%> <%=in%> <%=n2%> = <%=result%></p>
</body>
</html>