我有一个需要学生出勤的页面。它打印出一个学生列表,每个学生旁边都有一个复选框。然后该人单击提交并将所选学生的 ID 和实验室 ID 发送到数据库。
我遇到的问题是将最后一个勾选的框发送到数据库,其余的都没有。我假设它会覆盖它之前的那些,但我不确定如何解决这个问题。
这是我的doPost
方法:
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
int user_id = Integer.parseInt((String)request.getParameter("user_id"));
int lab_id = Integer.parseInt((String)request.getParameter("lab_id"));
System.out.println("I got a blow job");
String message = null;
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con =
DriverManager.getConnection("jdbc:mysql://localhost:3306/wae","root","");
System.out.println("got connection");
Statement s = con.createStatement();
String sql = "INSERT INTO user_lab" +
" (user_id, lab_id)" +
" VALUES" +
" ('" + user_id + "'," +
" '" + lab_id + "')";
System.out.println(sql);
int i = s.executeUpdate(sql);
if (i==1) {
message = "Successful attendance.";
response.sendRedirect("Tutor_labs");
}
s.close();
con.close();
}
catch (SQLException e) {
message = "Error." + e.toString();
boolean error = true;
}
catch (Exception e) {
message = "Error." + e.toString();
boolean error = true;
}
if (message!=null) {
PrintWriter out = response.getWriter();
out.println("<B>" + message + "</B><BR>");
out.println("<HR><BR>");
}
}
}
这是我的 JSP 页面:
<%@ 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>Mars University Lab System</title>
<link rel="stylesheet" href="style.css" type="text/css" media="screen">
</head>
<body>
<jsp:include page="headerTutor.jsp"/>
<div id = "centrecontent">
<h3>Students In Tutorial</h3>
<h2>Attendance List</h2>
<%
String[] list1 = (String[])request.getAttribute("res1");
String[] list2 = (String[])request.getAttribute("res2");
String[] list3 = (String[])request.getAttribute("res3");
String[] list4 = (String[])request.getAttribute("res4");
if(null == list1){%>
<th>Uni Id</th><th>Name</th><th>Email</th>
<%
}else{ %>
<form name="ViewStudentsTutor" ACTION="http://www.crackman.net.au/ICE/test.php\" method="post">
<% for(int i=0; i<list1.length; i++)
{
%> <input type="hidden" name="lab_id" value=<%=request.getParameter("labid")%>>
<%out.println(list2[i]);%>
<%out.println(list3[i]);%>
<%out.println(list4[i]); %>
<input type="checkbox" name="user_id" value=<%out.println(list1[i]);%>><br>
<% }}
%>
<input type="submit" value="Submit" name="Submit"/>
</form>
</div>
<jsp:include page="footer.jsp"/>
</body>
</html>