【发布时间】：2015-04-25 17:42:37
【问题描述】：
不久前我的代码运行良好，直到我的同学发送了一个修改过的 HTML 文件并且每个参数现在都为空。我真的不知道发生了什么。我将信息从表单传输到 servlet，从 servlet 传输到数据库。这是表单的代码：
<form method="post" action="informationTransfer">
<div class='row'>
<div class='col-md-6'>
<label for="username">User Name</label>
<input type="text" class="form-control" id="username" placeholder="User Name" name='username' required>
</div>
</div>
<br />
<div class='row'>
<div class='col-md-6'>
<label for="lastName">Last Name</label>
<input type="text" class="form-control" id="lastName" placeholder="Last Name" name='LastName' required>
</div>
<div class='col-md-6'>
<label for="firstName">Name</label>
<input type="text" class="form-control" id="firstName" placeholder="First Name" name='FirstName' required>
</div>
</div>
<br />
<div class='row'>
<div class='col-md-6'>
<label for="lastName">E-Mail</label>
<input type="email" class="form-control" id="email_1" placeholder="E-Mail Address" name='Email' required>
</div>
<div class='col-md-6'>
<label for="firstName">Confirm E-Mail</label>
<input type="email" class="form-control" id="email_2" placeholder="Confirm E-Mail Address" required>
</div>
</div>
<br />
<div class='row'>
<div class='col-md-6'>
<label for="lastName">Password</label>
<input type="password" class="form-control" id="password_1" placeholder="Password" name='Password' required>
</div>
<div class='col-md-6'>
<label for="firstName">Confirm Password</label>
<input type="password" class="form-control" id="password_2" placeholder="Confirm Password" required>
</div>
</div>
<br />
<div class='row'>
<div class='col-md-6'>
<label for='birthDate'>Birthday</label>
<div class="bfh-datepicker" data-max="today" data-close="false" data-date="today" data-format="y-m-d">
<input id="birthDate" type="text" data-name="birthDate" name='Birthdate' style='background-color:white;'>
</div>
</div>
<div class='col-md-6'>
<label for='gender'>Gender</label>
<select class='form-control' name='gender'>
<option>Male</option>
<option>Female</option>
</select>
</div>
</div>
<br />
<div class='row'>
<div class='col-md-4'>
<label for="countries_selectors">Country</label>
<select id="countries_selectors" class="form-control bfh-countries" data-country="PH" name='country' required></select>
</div>
<div class='col-md-4'>
<label for="State">State</label>
<select class="form-control bfh-states" data-country="countries_selectors" id='State' name='State' required></select>
</div>
<div class='col-md-4'>
<label for="zip">Zip Code</label>
<input type="zip" class="form-control" id="zip" placeholder="Zip Code" name='zipcode' required>
</div>
</div>
<br />
<div class='row'>
<div class='col-md-12'>
<label for="address">Home Address</label>
<input type="text" class="form-control" id="address" placeholder="Last Name" name='Address' required>
</select>
</div>
</div>
<br />
<div class='row'>
<div class='col-md-10'>
<label for="phone">Contact Number</label>
<input type="text" class="form-control bfh-phone" data-country="countries_selectors" id="phone" name='PhoneNumber'>
</div>
<div class='col-md-2'>
<label for="signup_b"><br /></label>
<button type="submit" class="btn btn-default center-block" name='signup_b'>Sign Up!</button>
</div>
</div>
</form>
这是 servlet 的代码：
@WebServlet(description = "transfers contents of bean to database", urlPatterns = { "/informationTransfer" })
public class transferInfo extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
toDatabase(request, response);
} catch (SQLException | ClassNotFoundException e) {
e.printStackTrace();
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
try {
toDatabase(request, response);
} catch (SQLException | ClassNotFoundException e) {
e.printStackTrace();
}
}
private void toDatabase(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException, SQLException, ClassNotFoundException
{
Class.forName("com.mysql.jdbc.Driver");
Connection con;
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/FoundationSystem","root","!Qaz2wsx");
con.setAutoCommit(false);
try
{
PreparedStatement stmt1, stmt2, stmt3;
stmt1 = con.prepareStatement("INSERT INTO AddressInformation (AddressID, Country, ZipCode, State, Address) VALUES (null,?,?,?,?)");
stmt1.setString(1, request.getParameter("country"));
stmt1.setString(2, request.getParameter("zipCode"));
stmt1.setString(3, request.getParameter("state"));
stmt1.setString(4, request.getParameter("address"));
stmt1.executeUpdate();
stmt2 = con.prepareStatement("INSERT INTO AccountDetails VALUES (?,?,?,?,?)");
stmt2.setString(1, request.getParameter("username"));
stmt2.setString(2, request.getParameter("password"));
stmt2.setString(3, null);
stmt2.setString(4, null);
stmt2.setInt(5, 3);
stmt2.executeUpdate();
stmt3 = con.prepareStatement("INSERT INTO PersonalInformation VALUES (?,?,?,?,?,?,?,?)");
Statement address = con.createStatement();
ResultSet result = address.executeQuery("SELECT max(AddressID) FROM AddressInformation");
result.next();
stmt3.setString(1, request.getParameter("userName"));
stmt3.setString(2, request.getParameter("lastName"));
stmt3.setString(3, request.getParameter("firstName"));
stmt3.setString(4, request.getParameter("gender"));
stmt3.setString(5, request.getParameter("birthdate"));
stmt3.setInt(6, result.getInt(1));
stmt3.setString(7, request.getParameter("email"));
stmt3.setString(8, request.getParameter("phoneNumber"));
stmt3.executeUpdate();
con.commit();
//response.sendRedirect();
}
catch (Exception e)
{
con.rollback();
System.out.println(e);
}
}
}
【问题讨论】：
-
您的输入名称属性以大写字母开头，并且您以小写形式获取它们，因此 stmt3.setString(3, request.getParameter("firstName"));应该是 stmt3.setString(3, request.getParameter("FirstName"));