我如何在会话中使用javascript变量以在另一个jsp页面中检索？

Question

This is my javaScript code where i'm getting student name and saving in session while retrieving in another jsp page its showing null? ' var studentName = document.getElementById("studentName").value; '<%Session["studentName"] = "' + studentName + '"; %>'; var studentName = document.getElementById("studentName").value; '<%Session["studentName"] = "' + studentName + '"; %>'; '

and i'm forwarding that page to next.jsp page as window.location.href="next.jsp" and i'm calling those values as ' String studentName = request.getParameter("studentName"); out.println(studentName); String studentName = request.getParameter("studentName"); out.println(studentName); '

in the javascript im getting correct value,and in next.jsp page its printing null value,what's mistake i'm doing?

Answer 1

You have set a session attribute in the first page and your are trying to get its value as if you are getting it from a submitted form.

While setting session in the previous page, use

session.setAttribute("session_attributename", studentName)

While getting the value in next page, use

session.getAttribute("session_attributename");

If you submit a form, then only you can use request.getParameter("....") to obtain the value in next page.

String studentName = request.getParameter("studentName");
out.println(studentName);

Answer 2

var studentName = document.getElementById("studentName").value;
window.location.href="next.jsp?studentName="+studentName;

in next.jsp

String studentName = request.getParameter("studentName");
out.println(studentName);

In this page you can store the name in session and once stored you can access the session value anywhere by using the session attribute name.

session.setAttribute("sname", studentName); (in next.jsp)

To get the Student name (in any page)

String studentName = (String)session.getAttribute("sname");