<h2>物品信息录入</h2>怎么放在页面正中间

要将<h2>物品信息录入</h2>放在页面正中间，你可以使用CSS样式来设置它的位置。可以使用以下CSS代码将它居中：

h2 {
  text-align: center;
  margin-top: 20%;
}

其中，text-align: center属性将文本居中对齐，而margin-top: 20%属性将它与页面顶部的距离设置为页面高度的20%，从而实现居中效果。

相关问题

<h2>物品信息录入</h2>怎么放在表单正上方

要将<h2>物品信息录入</h2>放在表单正上方，可以使用HTML和CSS来实现。以下是一种实现方式：

HTML代码：

<div class="form-wrapper">
  <h2>物品信息录入</h2>
  <form>
    <!-- 表单内容 -->
  </form>
</div>

CSS代码：

.form-wrapper {
  display: flex;
  flex-direction: column;
  align-items: center;
}

h2 {
  margin-top: 0;
}

这段代码将表单包裹在一个名为`form-wrapper`的`<div>`中，并将该`<div>`的`display`属性设置为`flex`，使其内部的元素能够进行灵活的布局。然后，通过`flex-direction: column`将子元素垂直排列，并通过`align-items: center`将它们居中对齐。

接着，通过给`h2`元素添加一个`margin-top: 0`来消除默认的上边距，使其能够与表单顶部对齐。

这样，就可以将<h2>物品信息录入</h2>放在表单正上方了。

Java录入车险信息的页面以及后台相关页面的代码

很抱歉，我无法为您提供完整的Java录入车险信息的页面和后台相关页面的代码，因为这需要根据具体的需求和技术栈进行设计和开发。不同的项目有不同的需求，采用的技术和代码实现也会有所不同。

不过，我可以为您提供一些参考代码，以帮助您了解Java录入车险信息的页面和后台相关页面的实现方式。

前端页面代码示例（使用HTML和JavaScript）：

<form id="car-insurance-form" action="#" method="post">
  <label for="car-brand">车辆品牌：</label>
  <input type="text" id="car-brand" name="carBrand" required>
  <br>
  <label for="car-model">车辆型号：</label>
  <input type="text" id="car-model" name="carModel" required>
  <br>
  <label for="car-number">车牌号：</label>
  <input type="text" id="car-number" name="carNumber" required>
  <br>
  <label for="insurance-start-date">保险起始日期：</label>
  <input type="date" id="insurance-start-date" name="insuranceStartDate" required>
  <br>
  <label for="insurance-end-date">保险结束日期：</label>
  <input type="date" id="insurance-end-date" name="insuranceEndDate" required>
  <br>
  <label for="insurance-type">保险类型：</label>
  <select id="insurance-type" name="insuranceType" required>
    <option value="">请选择保险类型</option>
    <option value="1">交强险</option>
    <option value="2">商业险</option>
  </select>
  <br>
  <button type="submit">提交</button>
</form>

<script>
  // 使用JavaScript对车牌号进行格式验证
  const carNumberInput = document.getElementById('car-number');
  carNumberInput.addEventListener('input', () => {
    const value = carNumberInput.value.trim().toUpperCase();
    if (!/^[A-Z]{1}[A-HJ-NP-Z]{1}\d{5}$/.test(value)) {
      carNumberInput.setCustomValidity('请输入正确的车牌号');
    } else {
      carNumberInput.setCustomValidity('');
    }
  });
</script>

后端页面代码示例（使用Java Servlet和JSP）：

@WebServlet("/car-insurance")
public class CarInsuranceServlet extends HttpServlet {
  private static final long serialVersionUID = 1L;
  private static final String DB_URL = "jdbc:mysql://localhost:3306/car_insurance";
  private static final String DB_USER = "root";
  private static final String DB_PASSWORD = "root";

  @Override
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    List<CarInsuranceInfo> carInsuranceList = getCarInsuranceList();
    request.setAttribute("carInsuranceList", carInsuranceList);
    request.getRequestDispatcher("/WEB-INF/car-insurance.jsp").forward(request, response);
  }

  @Override
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    String carBrand = request.getParameter("carBrand");
    String carModel = request.getParameter("carModel");
    String carNumber = request.getParameter("carNumber");
    String insuranceStartDate = request.getParameter("insuranceStartDate");
    String insuranceEndDate = request.getParameter("insuranceEndDate");
    String insuranceType = request.getParameter("insuranceType");

    saveCarInsuranceInfo(carBrand, carModel, carNumber, insuranceStartDate, insuranceEndDate, insuranceType);

    response.sendRedirect(request.getContextPath() + "/car-insurance");
  }

  private void saveCarInsuranceInfo(String carBrand, String carModel, String carNumber, String insuranceStartDate, String insuranceEndDate, String insuranceType) {
    try (Connection conn = DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD)) {
      String sql = "INSERT INTO car_insurance_info (car_brand, car_model, car_number, insurance_start_date, insurance_end_date, insurance_type) VALUES (?, ?, ?, ?, ?, ?)";
      try (PreparedStatement statement = conn.prepareStatement(sql)) {
        statement.setString(1, carBrand);
        statement.setString(2, carModel);
        statement.setString(3, carNumber);
        statement.setString(4, insuranceStartDate);
        statement.setString(5, insuranceEndDate);
        statement.setString(6, insuranceType);
        statement.executeUpdate();
      }
    } catch (SQLException ex) {
      ex.printStackTrace();
    }
  }

  private List<CarInsuranceInfo> getCarInsuranceList() {
    List<CarInsuranceInfo> carInsuranceList = new ArrayList<>();
    try (Connection conn = DriverManager.getConnection(DB_URL, DB_USER, DB_PASSWORD)) {
      String sql = "SELECT * FROM car_insurance_info";
      try (Statement statement = conn.createStatement();
           ResultSet resultSet = statement.executeQuery(sql)) {
        while (resultSet.next()) {
          int id = resultSet.getInt("id");
          String carBrand = resultSet.getString("car_brand");
          String carModel = resultSet.getString("car_model");
          String carNumber = resultSet.getString("car_number");
          String insuranceStartDate = resultSet.getString("insurance_start_date");
          String insuranceEndDate = resultSet.getString("insurance_end_date");
          String insuranceType = resultSet.getString("insurance_type");
          CarInsuranceInfo carInsuranceInfo = new CarInsuranceInfo(id, carBrand, carModel, carNumber, insuranceStartDate, insuranceEndDate, insuranceType);
          carInsuranceList.add(carInsuranceInfo);
        }
      }
    } catch (SQLException ex) {
      ex.printStackTrace();
    }
    return carInsuranceList;
  }
}

后端页面对应的JSP代码：

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <title>车险信息管理</title>
  <style>
    table {
      border-collapse: collapse;
    }

    td, th {
      border: 1px solid #ddd;
      padding: 8px;
    }
  </style>
</head>
<body>
  <h1>车险信息管理</h1>
  <form action="${pageContext.request.contextPath}/car-insurance" method="post">
    <label for="car-brand">车辆品牌：</label>
    <input type="text" id="car-brand" name="carBrand" required>
    <br>
    <label for="car-model">车辆型号：</label>
    <input type="text" id="car-model" name="carModel" required>
    <br>
    <label for="car-number">车牌号：</label>
    <input type="text" id="car-number" name="carNumber" required>
    <br>
    <label for="insurance-start-date">保险起始日期：</label>
    <input type="date" id="insurance-start-date" name="insuranceStartDate" required>
    <br>
    <label for="insurance-end-date">保险结束日期：</label>
    <input type="date" id="insurance-end-date" name="insuranceEndDate" required>
    <br>
    <label for="insurance-type">保险类型：</label>
    <select id="insurance-type" name="insuranceType" required>
      <option value="">请选择保险类型</option>
      <option value="1">交强险</option>
      <option value="2">商业险</option>
    </select>
    <br>
    <button type="submit">提交</button>
  </form>
  <hr>
  <h2>车险信息列表</h2>
  <table>
    <tr>
      <th>ID</th>
      <th>车辆品牌</th>
      <th>车辆型号</th>
      <th>车牌号</th>
      <th>保险起始日期</th>
      <th>保险结束日期</th>
      <th>保险类型</th>
    </tr>
    <c:forEach items="${carInsuranceList}" var="carInsurance">
      <tr>
        <td>${carInsurance.id}</td>
        <td>${carInsurance.carBrand}</td>
        <td>${carInsurance.carModel}</td>
        <td>${carInsurance.carNumber}</td>
        <td>${carInsurance.insuranceStartDate}</td>
        <td>${carInsurance.insuranceEndDate}</td>
        <td>${carInsurance.insuranceType == '1' ? '交强险' : '商业险'}</td>
      </tr>
    </c:forEach>
  </table>
</body>
</html>

以上代码示例仅供参考，实际项目中还需要根据具体需求进行调整和优化。