环境介绍
技术栈 | springboot+mybatis-plus+mysql |
软件 | 版本 |
mysql | 8 |
IDEA | IntelliJ IDEA 2022.2.1 |
JDK | 1.8 |
Spring Boot | 2.7.13 |
mybatis-plus | 3.5.3.2 |
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.7.15</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.example</groupId><artifactId>ajaxDemo01</artifactId><version>0.0.1-SNAPSHOT</version><name>ajaxDemo01</name><description>ajaxDemo01</description><properties><java.version>1.8</java.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>2.0.32</version></dependency><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.5.3.2</version></dependency><dependency><groupId>p6spy</groupId><artifactId>p6spy</artifactId><version>3.9.1</version></dependency><dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><scope>runtime</scope></dependency><dependency><groupId>com.alibaba</groupId><artifactId>druid</artifactId><version>1.2.15</version></dependency><dependency><groupId>com.baomidou</groupId><artifactId>dynamic-datasource-spring-boot-starter</artifactId><version>3.5.0</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.24</version></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build>
</project>
application.yml配置文件
spring:datasource:
# username: root
# password: 111111
# url: jdbc:p6spy:mysql://xxx.xxx.xxx.136:3306/sys?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=UTF-8
# driver-class-name: com.p6spy.engine.spy.P6SpyDriverdynamic:primary: sys #设置默认的数据源或者数据源组,默认值即为masterstrict: false #严格匹配数据源,默认false. true未匹配到指定数据源时抛异常,false使用默认数据源datasource:sys:username: rootpassword: 111111url: jdbc:p6spy:mysql://xxx.xxx.xxx.136:3306/sys?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=UTF-8driver-class-name: com.p6spy.engine.spy.P6SpyDriver
# driver-class-name: com.mysql.jdbc.Driverwms:url: jdbc:p6spy:mysql://xxx.xxx.xxx.136:3306/Wms?useUnicode=true&characterEncoding=UTF-8username: rootpassword: 111111driver-class-name: com.p6spy.engine.spy.P6SpyDriver
# driver-class-name: com.mysql.jdbc.Driversys2:username: rootpassword: 111111url: jdbc:p6spy:mysql://127.0.0.1:3306/sys?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=UTF-8driver-class-name: com.p6spy.engine.spy.P6SpyDriverserver:port: 8083mybatis-plus:configuration:#输出日志log-impl: org.apache.ibatis.logging.stdout.StdOutImpl#配置映射规则map-underscore-to-camel-case: true #表示支持下划线到驼蜂的映射#隐藏mybatis图标global-config:banner: falsedb-config:logic-delete-field: statuslogic-not-delete-value: 1logic-delete-value: 0
#
#mybatis:
# mapper-locations=classpath: com/example/dao/*.xml
数据库表
MybatisX逆向工程
逆向工程:通过数据库表接口,逆向生成java工程结构
实体类、mapper接口、mapper映射文件、Service接口、service实现类
domain(pojo)实体类
@Data
public class TArea implements Serializable {/*** */private Integer id;/*** */private String code;/*** */private String name;/*** */private String parentcode;private static final long serialVersionUID = 1L;
}
mapper(dao)接口
@Mapper
public interface TAreaMapper extends BaseMapper<TArea> {List<TArea> getALLParentcodeIsNull();List<TArea> getByParentcode(@Param("parentcode") String parentcode);}
mapper.xml映射文件
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.mapper.TAreaMapper"><resultMap id="BaseResultMap" type="com.example.domain.TArea"><id property="id" column="id" jdbcType="INTEGER"/><result property="code" column="code" jdbcType="VARCHAR"/><result property="name" column="name" jdbcType="VARCHAR"/><result property="parentcode" column="ParentCode" jdbcType="VARCHAR"/></resultMap><sql id="Base_Column_List">id,code,name,ParentCode</sql><select id="getALLParentcodeIsNull" resultType="com.example.domain.TArea">select * from t_area where ISNULL(ParentCode)</select><select id="getByParentcode" resultType="com.example.domain.TArea">select * from t_area where ParentCode =#{parentcode}</select>
</mapper>
service接口
public interface TAreaService extends IService<TArea> {List<TArea> getALLProvince();List<TArea> getByParentcode(String parentcode);
}
service实现类
@Service
@DS("sys2")
public class TAreaServiceImpl extends ServiceImpl<TAreaMapper, TArea>implements TAreaService{@Autowiredprivate TAreaMapper tAreaMapper;@Overridepublic List<TArea> getALLProvince() {return tAreaMapper.getALLParentcodeIsNull();}@Overridepublic List<TArea> getByParentcode(String parentcode) {return tAreaMapper.getByParentcode(parentcode);}
}
test测试类
@Test
void area(){//tAreaService.list();//tAreaService.getALLProvince();tAreaService.getByParentcode("001");
}
area.html前端页面
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body>
<script type="text/javascript" src="../js/jquery-3.4.1.js"></script><select id="province"><option value="">选择省份</option>
</select><select id="city"><option value="">选择城市</option>
</select><script type="text/javascript">$(document).ready(function () {$.ajax({type : "get",url :"/Area",dataType : "json",async :"false",//默认true ,异步success : function(data){for (var i=0; i<data.length;i++){let tr ="<option value='"+data[i].code+"'>"+data[i].name+"</option>";console.log(tr)$("#province").append(tr);}}})});$("#province").change(function () {let b=this.value;console.log(b)$.ajax({type : "GET",url :"/"+b+"/Area2",dataType : "json",async :"false",//默认true ,异步success : function(data){//清空原来的数据$("#city").empty();for (var i=0; i<data.length;i++){let tr ="<option value='"+data[i].code+"'>"+data[i].name+"</option>";console.log(tr)$("#city").append(tr);}}})})
</script>
</body>
</html>
controller控制层
@RequestMapping("/Area")
@ResponseBody
public List<TArea> Areademo() {List<TArea> allProvince = tAreaService.getALLProvince();return allProvince;
}@RequestMapping("/{code}/Area2")
@ResponseBody
public List<TArea> Areademo2(@PathVariable("code") String code) {List<TArea> allProvince = tAreaService.getByParentcode(code);return allProvince;
}
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以下为原理基础,可略
Ajax即Asynchronous Javascript And XML(异步JavaScript和XML)在 2005年被Jesse James Garrett提出的新术语,用来描述一种使用现有技术集合的‘新’方法,包括: HTML 或 XHTML, CSS, JavaScript, DOM, XML, XSLT, 以及最重要的XMLHttpRequest。使用Ajax技术网页应用能够快速地将增量更新呈现在用户界面上,而不需要重载(刷新)整个页面,这使得程序能够更快地回应用户的操作。
ajax基础
Xmlhttprequest对象是AJAX的核心对象,发送请求以及接收服务器数据的返回。
Xmlhttprequest对象,现代浏览器都是支持的,都内置了该对象。直接用即可。
XmlHttpRequest对象基本方法:
abort():停止发送当前请求
getAllResponseHeader():获取服务器的全部响应头
getResponseHeader("headerLabel”):根据响应头的名字,获取对应的响应头
open(“method”,”URL”,”[,asycFlag[,”userName”[,password]]]”):建立与服务器URL的连接,并设置请求的方法,以及是否使用异步请求。如果远程服务需要用户名、密 码,则 提供对应的信息。
send(content):发送请求。其中content是请求参数
setRequestHeader(“label”,”value”):在发送请求之前,先设置请求头
XMLHttpRequest对象的简单的属性:
onreadystatechange:该属性用于指定XMLHttpRequest对象状态改变时的事件处理函数。
readyState:该属性用于获取XMLHttpRequest对象处理状态
responseText:该属性用于获取服务器响应的XML文档对象
status:该属性是服务器返回的状态码,只有当服务器的响应已经完成时,才会有该状态码
statusText:该属性是服务器返回的状态文本信息,只有当服务器的响应已经完成时,才会有该状态文本信息。
XMLHttpRequest对象的readyState属性对应的状态值
0:请求未初始化
1:服务器连接已建立
2:请求已收到
3:正在处理请求
4:请求已完成且响应已就绪
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body>
<div id="mydiv"></div>
<input type="button" value="hello ajax" id="helloAjax">
<script type="text/javascript">window.onload = function (){document.getElementById("helloAjax").onclick =function (){// console.log("发送ajax请求")//1、创建ajax黑心对象XMLHttpRequestvar xhr =new XMLHttpRequest();//2、注册回调函数//该函数在XMLHttpRequestState状态值发生改变时被调用xhr.onreadystatechange = function () {//readyState是Ajax状态码/*** XMLHttpRequest对象的readyState属性对应的状态值* 0:请求未初始化* 1:服务器连接已建立* 2:请求已收到* 3:正在处理请求* 4:请求已完成且响应已就绪*/console.log(xhr.readyState)// if (this.readyState == 4){// console.log("响应结束")// }//status是http协议状态码console.log("http响应状态码"+this.status)if (this.status==404){alert("访问资源不存在")}if (this.status ==200){//将响应信息放到div图层中,渲染//innerHTML是javascript的元素属性,和ajax的XMLHttpRequest对象无关,innerText也是javascript的元素属性//innerHTML可以设置元素内部的HTML代码。document.getElementById("mydiv").innerHTML =this.responseText;document.getElementById("mydiv").innerText =this.responseText;}}//3、开启通道//open(method,url,async,user,psw)//method:请求方式,get,post//url:请求路径//async:true或false,true表示异步请求,false表示同步请求//user用户名//psw密码xhr.open("GET","/test01",true)//4、xhr.send()}}</script>
</body>
</html>