SpringMVC07——Ajax
Ajax
AJAX = Asynchronous JavaScript and XML（异步的 JavaScript 和 XML）。
AJAX 不是新的编程语言，而是一种使用现有标准的新方法。
AJAX 是与服务器交换数据并更新部分网页的艺术，在不重新加载整个页面的情况下。
使用ajax技术的网页，通过在后台服务器进行少量的数据交换，就可以实现异步局部更新。
JQuery使用相关
- 使用在线的CDN
<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
- 下载导入
<script
src="${pageContext.request.contextPath}/statics/js/jquery-3.1.1.min.js"></script>
Ajax的核心是XMLHttpRequest对象（XHR）。XHR为向服务器发送请求和解析服务器响应提供了接口。能够以一部方式从服务器获取新数据。
通过JQuery Ajax方法，能够使用Http Get和Http Post从远程服务器伤请求文本、HTML、XML或JSON，同时能够把这些外部数据直接载入网页的被选元素中。
1.配置web.xml和springmvc.xml
```xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
version="4.0">
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<filter>
<filter-name>encodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<session-config>
<session-timeout>15</session-timeout>
</session-config>
<welcome-file-list>
<welcome-file>login.jsp</welcome-file>
</welcome-file-list>
</web-app>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
https://www.springframework.org/schema/mvc/spring-mvc.xsd">
<!-- 配置SpringMVC -->
<!-- 1.开启SpringMVC注解驱动 -->
<mvc:annotation-driven/>
<!-- 2.静态资源默认servlet配置-->
<mvc:default-servlet-handler/>
<!-- 3.配置jsp 显示ViewResolver视图解析器 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
<!-- 前缀 -->
<property name="prefix" value="/WEB-INF/jsp/"/>
<!-- 后缀 -->
<property name="suffix" value=".jsp"/>
</bean>
<!-- 4.扫描web相关的bean -->
<context:component-scan base-package="com.pp.controller"/>
</beans>
- 编辑AjaxController
@RestController
public class AjaxController {
@RequestMapping("/a1")
public void ajax1(String name, HttpServletResponse response) throws IOException {
if ("admin".equals(name)) {
response.getWriter().print("true");
} else {
response.getWriter().print("false");
}
}
}
- 编辑index.js进行测试
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>$Title$</title>
<%--<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>--%>
<script src="${pageContext.request.contextPath}/statics/js/jquery-3.6.0.js"></script>
<script>
function a1(){
$.post({
url:"${pageContext.request.contextPath}/a1",
data:{'name':$("#txtName").val()},
success:function (data,status) {
alert(data);
alert(status);
}
});
}
</script>
</head>
<body>
<%--onblur：失去焦点触发事件--%>
用户名:<input type="text" id="txtName" onblur="a1()"/>
</body>
</html>
- 创建实体类User
@AllArgsConstructor
@Data
@NoArgsConstructor
public class User {
private String name;
private int age;
private String sex;
}
注册提示效果
需求：输入正确信息显示OK，如果信息不对显示重新输入
- 在控制器中添加
@RequestMapping("/a2")
public String ajax2(String name, String pwd) {
String msg = "";
//模拟数据库中存在数据
if (name != null) {
if ("admin".equals(name)) {
msg = "OK";
} else {
msg = "用户名输入错误";
}
}
if (pwd != null) {
if ("123456".equals(pwd)) {
msg = "OK";
} else {
msg = "密码输入有误";
}
}
return msg; //由于@RestController注解，将msg转成json格式返回
}
- 前端显示页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>ajax</title>
<script src="${pageContext.request.contextPath}/statics/js/jquery-3.6.0.js"></script>
<script>
function a1(){
$.post({
url:"${pageContext.request.contextPath}/a3",
data:{'name':$("#name").val()},
success:function (data) {
if (data.toString()=='OK'){
$("#userInfo").css("color","green");
}else {
$("#userInfo").css("color","red");
}
$("#userInfo").html(data);
}
});
}
function a2(){
$.post({
url:"${pageContext.request.contextPath}/a3",
data:{'pwd':$("#pwd").val()},
success:function (data) {
if (data.toString()=='OK'){
$("#pwdInfo").css("color","green");
}else {
$("#pwdInfo").css("color","red");
}
$("#pwdInfo").html(data);
}
});
}
</script>
</head>
<body>
<p>
用户名:<input type="text" id="name" onblur="a1()"/>
<span id="userInfo"></span>
</p>
<p>
密码:<input type="text" id="pwd" onblur="a2()"/>
<span id="pwdInfo"></span>
</p>
</body>
</html>
- 配置tomcat测试！
posted on 2021-05-11 10:33 JavaCoderPan 阅读(11) 评论(0) 编辑 收藏 举报 来源
