我正在创建一个测验应用程序。这里有 5 个 jsp 页面，有 5 个不同的测验。如果我使用 1 个 jsp 页面和结果页面，它工作正常......即；它从 QuizPage5.jsp 重定向并在 ResultPage.jsp 中显示结果。 我需要将 QuizPage1.jsp、QuizPage2.jsp、QuizPage3.jsp、QuizPage4.jsp 和 QuizPage5.jsp 的所有结果显示到 ResultPage.jsp。
我用过
在jsp1中传递值。
<form action="">
<input type="hidden" name="hidden" value="hidden">
<input type="submit" value="submit"></form>
在jsp2中获取值
String value=request.getParameter("hidden");
但是，我得到了java.lang.NullPointerException
这是我的代码..
QuizPage1.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script language="JavaScript">
function check()
{
var radio_choice = false;
for (counter = 0; counter < myform.grp.length; counter++)
{
if (myform.grp[counter].checked)
radio_choice = true;
}
if (!radio_choice)
{
alert("Please select one.")
return (false);
}
return(true);
}
</script>
</head>
<body>
<h3>Quiz No.1</h3>
Q1.Which one of the following is the Capital of India?<br><br>
<form action="QuizPage2.jsp" method="post" name="myform" onsubmit="return check();">
<input type="radio" name="grp" value="New Delhi" >New Delhi<br>
<input type="radio" name="grp" value="Kolkata" >Kolkata<br>
<input type="radio" name="grp" value="Chennai" >Chennai<br>
<input type="radio" name="grp" value="Mumbai" >Mumbai<br>
<br><br><input type="submit" value="Next Question">
<input type="hidden" name="hidden" value="grp">
<input type="submit" value ="Back" onclick="window.history.back();"/>
</form>
</body>
</html>
QuizPage2.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script language="JavaScript">
function check()
{
var radio_choice = false;
for (counter = 0; counter < myform2.grp2.length; counter++)
{
if (myform2.grp2[counter].checked)
radio_choice = true;
}
if (!radio_choice)
{
alert("Please select any one Answer");
return (false);
}
return(true);
}
</script>
</head>
<body>
<h3>Quiz No.2</h3>
Q2. Where is Chennai Located?<br><br>
<form action="QuizPage3.jsp"method="post" name="myform2" onsubmit="return check();">
<input type="radio" name="grp2" value="Karnataka" >Karnataka<br>
<input type="radio" name="grp2" value="Tamilnadu" >Tamilnadu<br>
<input type="radio" name="grp2" value="Andhra Pradesh" >Andhra Pradesh<br>
<input type="radio" name="grp2" value="Maharashtra" >Maharashtra<br>
<br><br><input type="submit" value="Next Question">
<input type="hidden" name="hidden" value="grp2">
<input type="submit" value ="Back" onclick="window.history.back();"/>
</form>
<%
String s1=request.getParameter("grp");
%>
</body>
</html>
QuizPage3.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script language="JavaScript">
function check()
{
var radio_choice = false;
for (counter = 0; counter < myform3.grp3.length; counter++)
{
if (myform3.grp3[counter].checked)
radio_choice = true;
}
if (!radio_choice)
{
alert("Please select any one Answer");
return (false);
}
return(true);
}
</script>
</head>
<body>
<h3>Quiz No.3</h3>
Q3. What is the largest state in the USA<br><br>
<form action="QuizPage4.jsp"method="post" name="myform" onsubmit="return check();">
<input type="radio" name="grp3" value="New York" >New York<br>
<input type="radio" name="grp3" value="Alaska" >Alaska<br>
<input type="radio" name="grp3" value="California" >California<br>
<input type="radio" name="grp3" value="Melbourne" >Melbourne<br>
<br><br><input type="submit" value="Next Question">
<input type="hidden" name="hidden" value="grp3">
<input type="submit" value ="Back" onclick="window.history.back();"/>
</form>
<%
String s2=request.getParameter("grp2");
%>
</body>
</html>
QuizPage4.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script language="JavaScript">
function check()
{
var radio_choice = false;
for (counter = 0; counter < myform4.grp4.length; counter++)
{
if (myform4.grp4[counter].checked)
radio_choice = true;
}
if (!radio_choice)
{
alert("Please select any one Answer");
return (false);
}
return(true);
}
</script>
</head>
<body>
<h3>Quiz No.4</h3>
Q4. The famous Dilwara Temples are situated in<br><br>
<form action="QuizPage5.jsp"method="post" name="myform" onsubmit="return check();">
<input type="radio" name="grp4" value="Uttar Pradesh" >Uttar Pradesh<br>
<input type="radio" name="grp4" value="Maharashtra" >Maharashtra<br>
<input type="radio" name="grp4" value="Andhra Pradesh" >Andhra Pradesh<br>
<input type="radio" name="grp4" value="Rajasthan" >Rajasthan<br>
<br><br><input type="submit" value="Next Question">
<input type="hidden" name="hidden" value="grp4">
<input type="submit" value ="Back" onclick="window.history.back();"/>
</form>
<%
String s3=request.getParameter("grp3");
%>
</body>
</html>
QuizPage5.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script language="JavaScript">
function check()
{
var radio_choice = false;
for (counter = 0; counter < myform5.grp5.length; counter++)
{
if (myform5.grp5[counter].checked)
radio_choice = true;
}
if (!radio_choice)
{
alert("Please select any one Answer");
return (false);
}
return(true);
}
</script>
</head>
<body>
<h3>Quiz No.5</h3>
Q5. The Indian Institute of Science is located at<br><br>
<form action="ResultPage.jsp"method="post" name="myform" onsubmit="return check();">
<input type="radio" name="grp5" value="Chennai" >Chennai<br>
<input type="radio" name="grp5" value="Bangalore" >Bangalore<br>
<input type="radio" name="grp5" value="Mumbai" >Mumbai<br>
<input type="radio" name="grp5" value="Hyderabad" >Hyderabad<br>
<br><br><input type="submit" value="Show Result">
<input type="hidden" name="hidden" value="grp5"/>
</form>
<%
String s4=request.getParameter("grp4");
%>
</body>
</html>
结果页.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Quiz Result</title>
</head>
<body>
<%
String answer="New Delhi";
String s1=request.getParameter("grp");
if(s1.equals(answer))
{
out.println("Correct Answer");
}
else
{out.println("Wrong Answer! The Correct Answer is :"+answer);
}
%>
<%
String answer2="Tamilnadu";
String s2=request.getParameter("grp2");
if(s2.equals(answer2))
{
out.println("Correct Answer");
}
else
{out.println("Wrong Answer! The Correct Answer is :"+answer2);
}
%>
<%
String answer3="Alaska";
String s3=request.getParameter("grp3");
if(s3.equals(answer3))
{
out.println("Correct Answer");
}
else
{out.println("Wrong Answer! The Correct Answer is :"+answer3);
}
%>
<%
String answer4="Rajasthan";
String s4=request.getParameter("grp4");
if(s4.equals(answer4))
{
out.println("Correct Answer");
}
else
{out.println("Wrong Answer! The Correct Answer is :"+answer4);
}
%>
<%
String answer5="Bangalore";
String s5=request.getParameter("grp5");
if(s5.equals(answer5))
{
out.println("Correct Answer");
}
else
{out.println("Wrong Answer! The Correct Answer is :"+answer5);
}
%>
</body>
</html>
非常感谢您的帮助。提前致谢
最佳答案
如果您希望可以跨多个页面访问数据，请考虑使用 session 来存储数据。例如，如果 page1.jsp 向 page2.jsp 提交表单参数“page1Result”，则在 page2.jsp 中执行以下操作:
String page1Result = request.getParameter("page1Result");
request.getSession().setAttribute("page1Result", page1Result);
然后在某个时刻(例如第 5 页)，您可以按如下方式访问 page1 值:
String page1Value = (String)request.getSession().getAttribute("page1Result);
================================================== =================================== 因此，将其应用到您的代码中:
在page2 jsp中，将文件末尾的scriptlet更改为:
<%
String s1=request.getParameter("grp");
request.getSession().setAttribute("s1", s1);
%>
在第 3 页 JSP 中，将脚本 let 更改为:
<%
String s2=request.getParameter("grp2");
request.getSession().setAttribute("s2", s2);
%>
等等。
最后在 ResultPage.jsp 上(仅显示答案 2 的一行示例)
out.println("Wrong Answer! The Correct Answer for question 2 is :"+session.getAttribute("s2"));
关于java - 如何将前一个jsp页面的值检索到结果页面？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/19993935/