Question

嗨朋友我试图通过链接将值从一个jsp传递到另一个jsp，但值没有传递。我在论坛中提到了很多答案。什么都没有帮助。

Display.jsp

<%@ page import="java.sql.*" %>
<%ResultSet resultset =null;%>

<HTML>
<HEAD>
    <TITLE>Select element drop down box</TITLE>
</HEAD>

<BODY>



<h2>EMPLOYEE DETAILS</h2>
<br>
<form  action = "Form.jsp">
<button type = "submit">Add New Employee</button>
</form>
<%
    try{
           Class.forName("com.mysql.jdbc.Driver").newInstance();

           Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/hirarchy_check","root","root@123");

           Statement statement = connection.createStatement() ; 

           resultset =statement.executeQuery(" SELECT e.Emp_Id,e.Emp_Name ,e.Emp_Designation, m.Emp_Designation"+
                  " FROM employee_details e " +
                   " INNER JOIN employee_details m on e.Manager_id = m.Emp_Id ") ;

%>
  <table border = 1>
              <tr><th>Employee Id</th><th>Employee Name</th><th>Employee Designation</th><th>Reporting Manager</th><th>View</th></tr>
              <tr><td>1</td><td>Steve</td><td>ceo</td><td>0</td><td><a href = 'FormUpdate.jsp'>View</a></td></tr>

  <%    
              while(resultset.next())
              { %>
                  <tr><td><%=resultset.getInt(1)%></td><td><%=resultset.getString(2)%></td>
                  <td><%=resultset.getString(3)%></td><td><%=resultset.getString(4)%></td>
                  <td><a href="EmpDetails.jsp?empId=${resultset.getInt(1)}&empName=${resultset.getString(2)}" >update</a></td></tr>
            <%  } %>

    </table>

<%         }
        catch(Exception e)
        {
             out.println(e);
        }
%>

</BODY>
</HTML>

我必须传递值的页面是

EmpDetails.jsp

  <%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!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=ISO-8859-1">
<title>Employee Details</title>
</head>
<body>
out.println<%=request.getParameter("empId") %>
out.println<%=request.getParameter("empName") %>
</body>
</html>

Answer 1

注意

要从以下答案运行代码，您必须包含JSTL代码库。它可以找到here。

或者要包含，请在JSP顶部写下以下行。

<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core" %>

<强>答案

你可以试试吗？

<c:forEach var="row" items="${resultset.rows}"> <tr> <td><a href="EmpDetails.jsp?empId=${row.Emp_Id}&empName=${row.Emp_Name}">update</a></td> </tr> </c:forEach>

Answer 2

如果您使用jsp到jsp重定向，请使用EL（表达式语言）并输入

${param.empId} <%=request.getParameter("empId") %>

${param.empName} <%=request.getParameter("empName") %>

您需要这样做，因为您正在从JSP重定向到JSP，而不是必需的......

从jsp传递值到jsp时获取null值

2 个答案: