程序
c.jsp：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body bgcolor = "#930047"><font size = 5>
随机分配给你一个1-100之间的数字，请猜！
<% int i = (int)(Math.random()*100+1);
session.setAttribute("count",new Integer(0));
session.setAttribute("save",new Integer(i));
%>
<BR><A HREF = "d.jsp">去猜这个数</A>
</font>
</body>
</html>
d.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<%@ taglib tagdir="/WEB-INF/tags" prefix="guessNumber"%>
<body bgcolor = cyan>
<font size=3 color="red"> <% String str = request.getParameter("guessNumber");
if(str==null)
str="*";
if(str.length()==0)
str="*";
%> <guessNumber:GuessTag number="<%=str %>" /> 当前猜测的结果是:<%=message %> <% if(message.startsWith("您猜对了")){%>
<br>
<a href="c.jsp">重新获得随机数</a>
<%} else{ %>
<form action="" method=post name=form>
<input type="text" name="guessNumber"> <input type="submit"
name="送出" name="submit">
</form> <%}%> </font>
</body>
</html>
GuessTag.tag
<%@ tag language="java" pageEncoding="UTF-8"%>
<%@ attribute name="number" required="true"%>
<%@ variable name-given="message" scope="AT_END"%>
<%
String mess = "";
Integer integer = (Integer)session.getAttribute("save");
int realnumber = integer.intValue();
int guessNumber = 0;
boolean boo = true;
try{
guessNumber = Integer.parseInt(number);
}
catch(Exception e){
boo = false;
}
if(boo){
if(guessNumber==realnumber){
int n = ((Integer)session.getAttribute("count")).intValue();
n=n+1;
session.setAttribute("count",new Integer(n));
mess = "您猜对了，这是第"+n+"次猜测";
}
else if(guessNumber>realnumber){
int n = ((Integer)session.getAttribute("count")).intValue();
n=n+1;
session.setAttribute("count",new Integer(n));
mess = "您猜大了，这是第"+n+"次猜测";
}
else if(guessNumber<realnumber){
int n = ((Integer)session.getAttribute("count")).intValue();
n=n+1;
session.setAttribute("count",new Integer(n));
mess = "您猜小了，这是第"+n+"次猜测";
}
else if(number.equals("你还没开始猜测")){
mess = "你还没开始猜测";
}
jspContext.setAttribute("message",mess);
}else
{
jspContext.setAttribute("message","请输入你的猜测");
}
%>
