如何使用javascript将servlet响应传递给html文本

Question

在我的项目中，我有 html 选择文件和 html 文本文件。我想显示一些在 html 选择文件选项 onchange 事件时访问 html 文本文件中的数据库的结果。为此，我编写了这个 servlet 代码，它从 access 数据库中获取数据并将结果发送到 jsp 页面。

package org.solr;

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class getValues
 */
@WebServlet("/getValues")
public class getValues extends HttpServlet {
    private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public getValues() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        String salesOrder=request.getParameter("salesOrder");
        System.out.println(salesOrder);
        try {
            Class.forName("net.ucanaccess.jdbc.UcanaccessDriver");
            String db_path="C:\\Users\\ftk1187\\Desktop\\ad\\Test1.accdb";
            Connection con=DriverManager.getConnection("jdbc:ucanaccess://"+db_path+";jackcessOpener=CryptCodecOpener","","12345tec");
            Statement state=con.createStatement();
            ResultSet rs=state.executeQuery("SELECT * FROM tblSO_all WHERE strSO='"+salesOrder+"'");
            while(rs.next())
            {
                String indDate=rs.getString("strDate");
                System.out.println(indDate);
                request.setAttribute("indDate", indDate);
                request.getRequestDispatcher("upload.jsp").forward(request, response);
            }
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub

    }
}

在jsp端，我写了这段javascript代码

<script>
function strSO(){
    var salesOrder=$("#sOrder option:selected").val();
    $.ajax({
        type:'get',
        url:'getValues',
        data:'salesOrder='+salesOrder,
        dataType:'text/plain',
        success:function(){
            console.log("success");
        }
    document.getElementById("indDate").value=<%=request.getAttribute("indDate")%>
    }); 
    }
</script>

servlet 运行正常，我在 eclipse 的控制台中使用 sysout 看到了结果。但结果未显示在 html 文本文件中。那么问题出在哪里？

更新

这是我的 Eclipse 控制台和浏览器控制台。

更新

经过斯瓦蒂的回答，问题的解决方法是这样的

String salesOrder=request.getParameter("salesOrder");
        try {
            Class.forName("net.ucanaccess.jdbc.UcanaccessDriver");
            String db_path="C:\\Users\\ftk1187\\Desktop\\ad\\Test1.accdb";
            Connection con=DriverManager.getConnection("jdbc:ucanaccess://"+db_path+";jackcessOpener=CryptCodecOpener","","12345tec");
            Statement state=con.createStatement();
            ResultSet rs=state.executeQuery("SELECT * FROM tblSO_all WHERE strSO='"+salesOrder+"'");
            while(rs.next())
            {
                String indDate=rs.getString("strDate");
                System.out.println(indDate);
                response.getWriter().write(indDate);
            }
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

还有这样的脚本

<script>
function salesOrder(){
    var salesOrder=$("#sOrder option:selected").val();
    $.ajax({
        type:'get',
        url:'getValues',
        data:'salesOrder='+salesOrder,
        success:function(data){
            console.log("success");
            document.getElementById("induction").value=data;
        }
    }); 
}
</script>

Answer 1

无论您将打印什么，即：System.out.println(indDate); 这将作为 ajax 调用中的响应返回。此外，您无法从 servlet 转发您的页面，因为您使用的是 ajax，您需要发回一些内容，然后您可以从那里转发.因此，从 servlet 中删除这些 request.getRequestDispatcher("upload.jsp").forward(request, response); 行。此外，您的 ajax 调用应如下所示：

function strSO(){
    var salesOrder=$("#sOrder option:selected").val();
    $.ajax({
        type:'get',
        url:'getValues',
        data:'salesOrder='+salesOrder,
        success:function(data){
            console.log("success");
       document.getElementById("indDate").value=data;//indDate will be asign to textbox
    //you can write redirect code  here
        }

    }); 
    }