java - 如何从数据库检索数据并使用jdbc连接在jsp文本字段中显示数据

我正在从数据库中检索数据并以JSP的形式显示在表中，但是我不知道如何在文本字段上显示它。

例如

当我搜索索引号时为

。

结果(名称，地址，年龄)必须进入我的JSP

中的文本字段

我的代码:

public class S2 extends HttpServlet {


protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    Connection conn = null;
    String url = "jdbc:mysql://localhost:3306/";
    String dbName = "shoppingCart";
    String driver = "com.mysql.jdbc.Driver";
    String userName = "root";
    String password = "";

    Statement st;
    try {
        Class.forName(driver).newInstance();
        conn = DriverManager.getConnection(url + dbName, userName, password);
        System.out.println("Connected!");
        String pid = request.getParameter("pid");

        ArrayList al = null;
        ArrayList pid_list = new ArrayList();
        String query = "select * from user where uid='" + pid + "' ";

        System.out.println("query " + query);
        st = conn.createStatement();
        ResultSet rs = st.executeQuery(query);

        while (rs.next()) {

            al = new ArrayList();

            out.println(rs.getString(1));
            out.println(rs.getString(2));
            out.println(rs.getString(3));
            out.println(rs.getString(4));
            out.println(rs.getString(5));


            al.add(rs.getString(1));
            al.add(rs.getString(2));
            al.add(rs.getString(3));
            al.add(rs.getString(4));
            al.add(rs.getString(5));


            System.out.println("al :: " + al);
            pid_list.add(al);
        }


        request.setAttribute("piList", pid_list);
        RequestDispatcher view = request.getRequestDispatcher("/searchview.jsp");
        view.forward(request, response);
        conn.close();
        System.out.println("Disconnected!");
    } catch (Exception e) {
        e.printStackTrace();
    }

最佳答案

确保在项目中包含了jdbc驱动程序，并对其进行“构建”。然后:

建立数据库连接并检索查询结果。

返回查询结果并保存在ResultSet对象中。

遍历对象并显示查询结果。

下面的示例代码详细说明了这一点。

String label = request.getParameter("label");
//retrieving a variable from a previous page

Connection dbc = null; //Make connection to the database
Class.forName("com.mysql.jdbc.Driver");
dbc = DriverManager.getConnection("jdbc:mysql://localhost:3306/works", "root", "root");

if (dbc != null)
{
    System.out.println("Connection successful");
}
ResultSet rs = listresult.dbresult.func(dbc, label);
//The above function is mentioned in the end.
//It is defined in another package- listresult

while (rs.next())
{
%>
<form name="demo form" method="post">
    <table>
        <tr>
            <td>
                Label Name:
            </td>
            <td>
                <input type="text" name="label"
                value="<%=rs.getString("lname")%>">
            </td>
        </tr>
    </table>
</form>
<% } %>


public static ResultSet func(Connection dbc, String x)
{
    ResultSet rs = null;
    String sql;
    PreparedStatement pst;
    try
    {
        sql = "select lname from demo where label like '" + x + "'";
        pst = dbc.prepareStatement(sql);
        rs = pst.executeQuery();
    }
    catch (Exception e)
    {
        e.printStackTrace();
        String sqlMessage = e.getMessage();
    }
    return rs;
}

我试图使这个例子尽可能详细。如果有任何疑问，请询问。