springmvc-ajax

先配置web.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>DispatcherServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:applicationContext.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>DispatcherServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>


    <!--防止中文乱码-->
    <filter>
        <filter-name>encoding</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>encoding</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>

maven依赖

这里选择spring的4.2.2可以选择5.2

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>SpringMVC</artifactId>
        <groupId>com.rzk</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>sppringmvc-06-ajax01</artifactId>
    <!--导入依赖-->
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.2.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.2</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.1</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>
    </dependencies>
    资源过滤
    <build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>

    </build>

</project>

applicationContext.xml配置文件

<?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
       http://www.springframework.org/schema/mvc/spring-mvc.xsd">
    <!--自动扫描包,下面所有注解类叫给IOC容器管理-->
    <context:component-scan base-package="com.rzk.controller"/>
    <!--注解驱动-->
    <mvc:annotation-driven/>
    <!--静态资源过滤-->
    <mvc:default-servlet-handler/>
    <!--视图解析器-->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/"/>
        <property name="suffix" value=".jsp"/>
    </bean>
</beans>

接下来新建controller包

@RestController
public class AjaxController {

    @RequestMapping("/a3")
    public String test3(String name,String pwd){
        String msg = null;
        if (name !=null){
            if ("admin".equals(name)){
                msg = "OK";
            }else{
                msg ="No";
            }
        }
        if (pwd !=null){
            if ("admin".equals(pwd)){
                msg = "OK";
            }else{
                msg ="No";
            }
        }
        return msg;
    }

}

login.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
    <script src="/js/jquery-3.3.1.min.js"></script>
    <script>
        function a1(){
            $.post({
                url:"${pageContext.request.contextPath}/a3",
                data:{"name":$("#name").val()},
                success:function (data) {
                    console.log(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){
                    console.log(data)
                }
            })
        }

    </script>

</head>
<body>
账号:<input type="text" id="name" name="name" onblur="a1()">
<span id="userInfo"></span>
密码:<input type="text" id="pwd" name="pwd" onblur="a2()">
<span id="pwdInfo"></span>
</body>
</html>

下面使用ajax获取后端数据显示到前台

新建实体类,导入lombok

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private String name;
    private int age;
    private String sex;
}

controller

@RestController
public class AjaxController {
 @RequestMapping("/a2")
    public List<User> test2(){
        ArrayList<User> list = new ArrayList<>();
        list.add(new User("李四",1,"男"));
        list.add(new User("李五",2,"男"));
        list.add(new User("李六",3,"男"));
        return list;
    }
}

前端ajax页面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
    <script src="${pageContext.request.contextPath}/js/jquery-3.3.1.min.js"></script>
    <script type="text/javascript">
        $(function () {
            $("#a").click(function () {
                $.post(
                    "${pageContext.request.contextPath}/a2",function(data) {
                        console.log(data[2])
                        var html = "<>";
                        for (let i = 0; i < data.length ; i++) {
                            html += "<tr>" +
                                "<td>" + data[i].name + "</td>" +
                                "<td>" + data[i].age + "</td>" +
                                "<td>" + data[i].sex + "</td>" +
                                "<tr>"
                        }
                        $("#content").html(html);
                    });
            })
        })
    </script>
</head>
<body>
<input type="button" value="加载数据" id="a">
    <table>
        <tr>
            <td>姓名</td>
            <td>年龄</td>
            <td>性别</td>
        </tr>
        <tbody id="content">

        </tbody>
    </table>
</body>
</html>