AJAX实现数据的增删改查操作详解【java后台】

(编辑：jimmy 日期: 2024/5/9 浏览：3 次 )
本文实例讲述了AJAX实现数据的增删改查操作。分享给大家供大家参考，具体如下：
主页：index.html
<!DOCTYPE html>
<html>
 <head>
 <meta charset="UTF-8">
 <title></title>
 <script src="/UploadFiles/2021-04-02/jquery.min.js">

增加的Serlvet：Hello.java


package com.web;
 
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import com.mysql.MysqlUtil;
 
/**
 * Servlet implementation class Hello
 */
@WebServlet("/Hello")
public class Hello extends HttpServlet {
 private static final long serialVersionUID = 1L;
    
  /**
   * @see HttpServlet#HttpServlet()
   */
  public Hello() {
    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
 response.getWriter().append("Served at: ").append(request.getContextPath());
 }
 
 /**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 
 response.setCharacterEncoding("utf-8");
 response.setContentType("application/json; charset=utf-8");
 
 String pno = request.getParameter("pno");
 String name = request.getParameter("name");
 String sex = request.getParameter("sex");
 String age = request.getParameter("age");
 String height = request.getParameter("height");
 String weight = request.getParameter("weight");
 
 String sqlInsert = "INSERT INTO Person (Pno,Pname,Psex,Page,Pheight,Pweight) VALUES('";
 sqlInsert += pno +"','";
 sqlInsert += name +"','";
 sqlInsert += sex +"',";
 sqlInsert += age +",";
 sqlInsert += height +",";
 sqlInsert += weight +")";
 
 int message = MysqlUtil.add(sqlInsert);
 String rep = "";
 if(message == 1) {
  rep = "{\"code\":200,\"message\":\"成功插入数据库\"}";
 }else {
  rep = "{\"code\":\"999\",\"message\":\"插入失败了\"}";
 }
 response.getWriter().write(rep);
 
 
 }
 
}



删除的Servlet：HelloDelete.java


package com.web;
 
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import com.mysql.MysqlUtil;
 
/**
 * Servlet implementation class HelloDelete
 */
@WebServlet("/HelloDelete")
public class HelloDelete extends HttpServlet {
 private static final long serialVersionUID = 1L;
    
  /**
   * @see HttpServlet#HttpServlet()
   */
  public HelloDelete() {
    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
 response.getWriter().append("Served at: ").append(request.getContextPath());
 }
 
 /**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
 response.setCharacterEncoding("utf-8");
 response.setContentType("application/json; charset=utf-8");
 
 String pno = request.getParameter("pno");
 
 
 String sqlDel = "delete from Person where pno="+pno;
 
 
 int message = MysqlUtil.del(sqlDel);
 String rep = "";
 if(message == 1) {
  rep = "{\"code\":\"200\",\"message\":\"成功删除\"}";
 }else {
  rep = "{\"code\":\"999\",\"message\":\"删除失败\"}";
 }
 response.getWriter().write(rep);
 }
 
}



更新的Servlet：HelloUpdate.java


package com.web;
 
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import com.mysql.MysqlUtil;
 
/**
 * Servlet implementation class HelloUpdate
 */
@WebServlet("/HelloUpdate")
public class HelloUpdate extends HttpServlet {
 private static final long serialVersionUID = 1L;
    
  /**
   * @see HttpServlet#HttpServlet()
   */
  public HelloUpdate() {
    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
 response.getWriter().append("Served at: ").append(request.getContextPath());
 }
 
 /**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
 response.setCharacterEncoding("utf-8");
 response.setContentType("application/json; charset=utf-8");
 
 String pno = request.getParameter("pno");
 String name = request.getParameter("name");
 String sex = request.getParameter("sex");
 String age = request.getParameter("age");
 String height = request.getParameter("height");
 String weight = request.getParameter("weight");
 
 String sqlupdate = "update Person set ";
// sqlupdate += "Pno='"+ pno +"',";
 sqlupdate += "Pname='"+ name +"',";
 sqlupdate += "Psex='"+ sex +"',";
 sqlupdate += "Page="+ age +",";
 sqlupdate += "Pheight="+ height +",";
 sqlupdate += "Pweight="+ weight;
 sqlupdate += " where Pno='"+pno+"'";
 System.out.println(sqlupdate);
 int message = MysqlUtil.update(sqlupdate);
 String rep = "";
 if(message == 1) {
  rep = "{\"code\":\"200\",\"message\":\"成功插入数据库\"}";
 }else {
  rep = "{\"code\":\"999\",\"message\":\"插入失败了\"}";
 }
 response.getWriter().write(rep);
 
 }
 
}



查询的Servlet：HelloQuery.java


package com.web;
 
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
 
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import com.mysql.MysqlUtil;
 
/**
 * Servlet implementation class HelloQuery
 */
@WebServlet("/HelloQuery")
public class HelloQuery extends HttpServlet {
 private static final long serialVersionUID = 1L;
    
  /**
   * @see HttpServlet#HttpServlet()
   */
  public HelloQuery() {
    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
 response.getWriter().append("Served at: ").append(request.getContextPath());
 }
 
 /**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
 response.setCharacterEncoding("utf-8");
 response.setContentType("application/json; charset=utf-8");
 String pno = request.getParameter("pno");
 String[] params = {"Pno","Pname","Psex","Page","Pheight","Pweight"};
 String sql = "select * from Person where Pno="+pno;
 String data = "{";
 
 String[] str = {"编号","姓名","性别","年龄","身高","体重"};
 List<Map<String,String listmap = new ArrayList<>();
 listmap = MysqlUtil.show(sql, params);
 for(int i =0 ; i<listmap.size();i++) {  
  for(int j=0 ; j<listmap.get(i).size();j++) {
  data += "\""+str[j]+"\":"+"\""+listmap.get(i).get(params[j])+"\",";  
  }
 }
 data = data.substring(0, data.length()-1);
 data += "}";
 
 
 System.out.println(data);
 response.getWriter().write(data);
 }
 
 
 
}



页面如下：

对应的数据库：

 git克隆地址：https://github.com/dreamiboy/JDBCUtil.git
更多关于ajax相关内容感兴趣的读者可查看本站专题：《jquery中Ajax用法总结》、《JavaScript中ajax操作技巧总结》、《PHP+ajax技巧与应用小结》及《asp.net ajax技巧总结专题》
希望本文所述对大家ajax程序设计有所帮助。
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