前言：

小编讲述了参数传递，返回值以及页面跳转！为我们的CRUD提供了理论基础，接下来小编会通过SpringMvc实现CRUD来讲述在企业开发中必须要学会的CRUD

一.前期环境搭建

1.替换pom.xml的内容

<properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <maven.compiler.plugin.version>3.7.0</maven.compiler.plugin.version>

        <!--添加jar包依赖-->
        <!--1.spring 5.0.2.RELEASE相关-->
        <spring.version>5.0.2.RELEASE</spring.version>
        <!--2.mybatis相关-->
        <mybatis.version>3.4.5</mybatis.version>
        <!--mysql-->
        <mysql.version>5.1.44</mysql.version>
        <!--pagehelper分页jar依赖-->
        <pagehelper.version>5.1.2</pagehelper.version>
        <!--mybatis与spring集成jar依赖-->
        <mybatis.spring.version>1.3.1</mybatis.spring.version>
        <!--3.dbcp2连接池相关 druid-->
        <commons.dbcp2.version>2.1.1</commons.dbcp2.version>
        <commons.pool2.version>2.4.3</commons.pool2.version>
        <!--4.log日志相关-->
        <log4j2.version>2.9.1</log4j2.version>
        <log4j2.disruptor.version>3.2.0</log4j2.disruptor.version>
        <slf4j.version>1.7.13</slf4j.version>
        <!--5.其他-->
        <junit.version>4.12</junit.version>
        <servlet.version>4.0.0</servlet.version>
        <lombok.version>1.18.2</lombok.version>

        <mybatis.ehcache.version>1.1.0</mybatis.ehcache.version>
        <ehcache.version>2.10.0</ehcache.version>

        <redis.version>2.9.0</redis.version>
        <redis.spring.version>1.7.1.RELEASE</redis.spring.version>
        <jackson.version>2.9.3</jackson.version>
        <jstl.version>1.2</jstl.version>
        <standard.version>1.1.2</standard.version>
        <tomcat-jsp-api.version>8.0.47</tomcat-jsp-api.version>
        <commons-fileupload.version>1.3.3</commons-fileupload.version>
        <hibernate-validator.version>5.0.2.Final</hibernate-validator.version>

        <shiro.version>1.3.2</shiro.version>
    </properties>

 

   <dependencies>
        <!--1.spring相关-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
        </dependency>


        <!--2.mybatis相关-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>${mybatis.version}</version>
        </dependency>
        <!--mysql-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql.version}</version>
        </dependency>
        <!--pagehelper分页插件jar包依赖-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper</artifactId>
            <version>${pagehelper.version}</version>
        </dependency>
        <!--mybatis与spring集成jar包依赖-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>${mybatis.spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <!--mybatis与ehcache整合-->
        <dependency>
            <groupId>org.mybatis.caches</groupId>
            <artifactId>mybatis-ehcache</artifactId>
            <version>${mybatis.ehcache.version}</version>
        </dependency>
        <!--ehcache依赖-->
        <dependency>
            <groupId>net.sf.ehcache</groupId>
            <artifactId>ehcache</artifactId>
            <version>${ehcache.version}</version>
        </dependency>

        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
            <version>${redis.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-redis</artifactId>
            <version>${redis.spring.version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>${jackson.version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>${jackson.version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>${jackson.version}</version>
        </dependency>

        <!--3.dbcp2连接池相关-->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-dbcp2</artifactId>
            <version>${commons.dbcp2.version}</version>
            <exclusions>
                <exclusion>
                    <artifactId>commons-pool2</artifactId>
                    <groupId>org.apache.commons</groupId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
            <version>${commons.pool2.version}</version>
        </dependency>

        <!--springmvc依赖-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <!--4.log日志相关依赖-->

        <!-- log4j2日志相关依赖 -->
        <!-- log配置：Log4j2 + Slf4j -->
        <!-- slf4j核心包-->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>${slf4j.version}</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>jcl-over-slf4j</artifactId>
            <version>${slf4j.version}</version>
            <scope>runtime</scope>
        </dependency>

        <!--核心log4j2jar包-->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>${log4j2.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>${log4j2.version}</version>
        </dependency>
        <!--用于与slf4j保持桥接-->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j-impl</artifactId>
            <version>${log4j2.version}</version>
        </dependency>
        <!--web工程需要包含log4j-web，非web工程不需要-->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-web</artifactId>
            <version>${log4j2.version}</version>
            <scope>runtime</scope>
        </dependency>

        <!--需要使用log4j2的AsyncLogger需要包含disruptor-->
        <dependency>
            <groupId>com.lmax</groupId>
            <artifactId>disruptor</artifactId>
            <version>${log4j2.disruptor.version}</version>
        </dependency>

        <!--5.其他-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>${servlet.version}</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>${lombok.version}</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>jstl</groupId>
            <artifactId>jstl</artifactId>
            <version>${jstl.version}</version>
        </dependency>
        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>${standard.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-jsp-api</artifactId>
            <version>${tomcat-jsp-api.version}</version>
        </dependency>
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>${commons-fileupload.version}</version>
        </dependency>

        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>${hibernate-validator.version}</version>
        </dependency>

        <!--shiro依赖-->
        <dependency>
            <groupId>org.apache.shiro</groupId>
            <artifactId>shiro-core</artifactId>
            <version>${shiro.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.shiro</groupId>
            <artifactId>shiro-web</artifactId>
            <version>${shiro.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.shiro</groupId>
            <artifactId>shiro-spring</artifactId>
            <version>${shiro.version}</version>
        </dependency>
    </dependencies>

2.导入配置文件(小编上传资源)

 3.修改xml文件

<?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_3_1.xsd"
         version="3.1">
  <display-name>Archetype Created Web Application</display-name>
  <!-- Spring和web项目集成start -->
  <!-- spring上下文配置文件 -->
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring-context.xml</param-value>
  </context-param>
  <!-- 读取Spring上下文的监听器 -->
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <!-- Spring和web项目集成end -->

  <!-- 中文乱码处理 -->
  <filter>
    <filter-name>encodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <async-supported>true</async-supported>
    <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>

  <!-- Spring MVC servlet -->
  <servlet>
    <servlet-name>SpringMVC</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!--此参数可以不配置，默认值为：/WEB-INF/springmvc-servlet.xml-->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:spring-mvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
    <!--web.xml 3.0的新特性，是否支持异步-->
    <async-supported>true</async-supported>
  </servlet>
  <servlet-mapping>
    <servlet-name>SpringMVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

4.点击创建自动生成代码

在book的类里面重写tostring方法！

5.写一个类用于处理页面跳转

package com.lz.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * @author lz
 * @create 2023-09-07 16:21
 */
@Controller
public class PageController {

    @RequestMapping("/page/{page}")
    public   String  toPage(@PathVariable("page")String page){

        return  page;
    }


    @RequestMapping("/page/{dir}{page}")
    public   String  toDirPage(@PathVariable("dir")String dir,
                               @PathVariable("page")String page ){

        return  dir + "/" +  page;
    }
}

二.正式启动SpringMVC的CRUD

1.建立接口，调用自动生成的接口

package com.lz.Biz;

import com.lz.model.Book;
import com.lz.utlis.PageBean;

import java.util.List;

public interface BookBiz {
    int deleteByPrimaryKey(Integer bid);

    int insert(Book record);

    int insertSelective(Book record);

    Book selectByPrimaryKey(Integer bid);

    int updateByPrimaryKeySelective(Book record);

    int updateByPrimaryKey(Book record);

    List<Book>listPager (Book  book, PageBean  pageBean);
}

实现接口的方法，并且用@serverce注解被spring管理，@Autowries调用Book.xml

文件

package com.lz.Biz;

import com.lz.mapper.BookMapper;
import com.lz.model.Book;
import com.lz.utlis.PageBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * @author lz
 * @create 2023-09-08 9:32
 *
 */
@Service
public class BookBizImpl    implements   BookBiz{
    @Autowired
    private BookMapper  bookMapper;
    @Override
    public int deleteByPrimaryKey(Integer bid) {
        return bookMapper.deleteByPrimaryKey(bid) ;
    }

    @Override
    public int insert(Book record) {
        return bookMapper.insert(record);
    }

    @Override
    public int insertSelective(Book record) {
        return bookMapper.insertSelective(record);
    }

    @Override
    public Book selectByPrimaryKey(Integer bid) {
        return bookMapper.selectByPrimaryKey(bid);
    }

    @Override
    public int updateByPrimaryKeySelective(Book record) {
        return bookMapper.updateByPrimaryKey(record);
    }

    @Override
    public int updateByPrimaryKey(Book record) {
        return bookMapper.updateByPrimaryKey(record);
    }

    @Override
    public List<Book> listPager(Book book, PageBean pageBean) {
         return bookMapper.listPager(book);
}

2.构建分页代码

2.1书写BookMapper.xml中分页的方法

  <select id="listPager" resultType="com.lz.model.Book" parameterType="com.lz.model.Book" >
    select
    <include refid="Base_Column_List" />
    from t_mvc_book
    <where>
      <if test="bname !=null">
        and  cname  like  concat ('%',#{bname},'%')
      </if>
    </where>
  </select>

2.2调用分页的方法

List<Book> listPager(Book  book);

2.3导入一个工具类用于分页实现

package com.lz.tag;

import com.lz.utlis.PageBean;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;


public class PageTag extends BodyTagSupport{
	private PageBean pageBean;// 包含了所有分页相关的元素
	
	public PageBean getPageBean() {
		return pageBean;
	}

	public void setPageBean(PageBean pageBean) {
		this.pageBean = pageBean;
	}

	@Override
	public int doStartTag() throws JspException {
//		没有标签体，要输出内容
		JspWriter out = pageContext.getOut();
		try {
			out.print(toHTML());
		} catch (IOException e) {
			e.printStackTrace();
		}
		return super.doStartTag();
	}

	private String toHTML() {
		StringBuffer sb = new StringBuffer();
//		隐藏的form表单---这个就是上一次请求下次重新发的奥义所在
//		上一次请求的URL
		sb.append("<form action='"+pageBean.getUrl()+"' id='pageBeanForm' method='post'>");
		sb.append("	<input type='hidden' name='page'>");
//		上一次请求的参数
		Map<String, String[]> paramMap = pageBean.getMap();
		if(paramMap != null && paramMap.size() > 0) {
			Set<Entry<String, String[]>> entrySet = paramMap.entrySet();
			for (Entry<String, String[]> entry : entrySet) {
//				参数名
				String key = entry.getKey();
//				参数值
				for (String value : entry.getValue()) {
//					上一次请求的参数，再一次组装成了新的Form表单
//					注意：page参数每次都会提交，我们需要避免
					if(!"page".equals(key)) {
						sb.append("	<input type='hidden' name='"+key+"' value='"+value+"' >");
					}
				}
			}
		}
		sb.append("</form>");
		
//		分页条
		sb.append("<ul class='pagination justify-content-center'>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == 1 ? "disabled" : "")+"'><a class='page-link'");
		sb.append("	href='javascript:gotoPage(1)'>首页</a></li>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == 1 ? "disabled" : "")+"'><a class='page-link'");
		sb.append("	href='javascript:gotoPage("+pageBean.getPreivousPage()+")'>&lt;</a></li>");// less than 小于号
//		sb.append("	<li class='page-item'><a class='page-link' href='#'>1</a></li>");
//		sb.append("	<li class='page-item'><a class='page-link' href='#'>2</a></li>");
		sb.append("	<li class='page-item active'><a class='page-link' href='#'>"+pageBean.getPage()+"</a></li>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == pageBean.getMaxPage() ? "disabled" : "")+"'><a class='page-link' href='javascript:gotoPage("+pageBean.getNextPage()+")'>&gt;</a></li>");
		sb.append("	<li class='page-item "+(pageBean.getPage() == pageBean.getMaxPage() ? "disabled" : "")+"'><a class='page-link' href='javascript:gotoPage("+pageBean.getMaxPage() +")'>尾页</a></li>");
		sb.append("	<li class='page-item go-input'><b>到第</b><input class='page-link'");
		sb.append("	type='text' id='skipPage' name='' /><b>页</b></li>");
		sb.append("	<li class='page-item go'><a class='page-link'");
		sb.append("	href='javascript:skipPage()'>确定</a></li>");
		sb.append("	<li class='page-item'><b>共"+pageBean.getTotal()+"条</b></li>");
		sb.append("</ul>");
		
//		分页执行的JS代码
		sb.append("<script type='text/javascript'>");
		sb.append("	function gotoPage(page) {");
		sb.append("		document.getElementById('pageBeanForm').page.value = page;");
		sb.append("		document.getElementById('pageBeanForm').submit();");
		sb.append("	}");
		sb.append("	function skipPage() {");
		sb.append("		var page = document.getElementById('skipPage').value;");
		sb.append("		if (!page || isNaN(page) || parseInt(page) < 1 || parseInt(page) > "+pageBean.getMaxPage()+") {");
		sb.append("			alert('请输入1~"+pageBean.getMaxPage()+"的数字');");
		sb.append("			return;");
		sb.append("		}");
		sb.append("		gotoPage(page);");
		sb.append("	}");
		sb.append("</script>");
		
		return sb.toString();
	}
}

2.4导入一个tid文件用于分页实现

<?xml version="1.0" encoding="UTF-8" ?>

<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
    version="2.0">
    
  <description>zking 1.1 core library</description>
  <display-name>zking core</display-name>
  <tlib-version>1.1</tlib-version>
  <short-name>zking</short-name>
  <uri>http://jsp.veryedu.cn</uri>
  
  
  <tag>
    <name>page</name>
    <tag-class>com.lz.tag.PageTag</tag-class>
    <body-content>JSP</body-content>
    <attribute>
        <name>pageBean</name>
        <required>true</required>
        <rtexprvalue>true</rtexprvalue>
    </attribute>
  </tag>
  
</taglib>

3.实现后端功能

3.1构建功能实现代码

package com.lz.controller;

import com.lz.Biz.BookBiz;
import com.lz.model.Book;
import com.lz.utlis.PageBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.servlet.http.HttpServletRequest;
import java.util.List;

/**
 * @author lz
 * @create 2023-09-08 16:20
 */
@Controller
@RequestMapping("/book")
public class BookController {
    @Autowired
    private   BookBiz  bookBiz;
      //增加
    @RequestMapping("/add")
    public     String  add(Book  book){
        int i = bookBiz.insertSelective(book);
        return  "redirect:list";
    }
     //删除
     @RequestMapping("/del/{bid}")
     public     String  del(@PathVariable("bid")Integer bid){
         int i = bookBiz.deleteByPrimaryKey(bid);
         return  "redirect:/book/list";
     }
    //修改
    @RequestMapping("/edit")
    public   String edit(Book  book){
        int i = bookBiz.updateByPrimaryKeySelective(book);
        return  "redirect:list";
    }
     // 查询
    @RequestMapping("/list")
    //Book接收前台传递的参数
    public  String list(Book  book  , HttpServletRequest  request){
        PageBean  pageBean=new PageBean();
        pageBean.setRequest(request);
        List<Book> books = bookBiz.listPager(book, pageBean);
        request.setAttribute("lst",books);
        request.setAttribute("pageBean",pageBean);
        return "book/list";
    }
     //数据回显
    @RequestMapping("/preSave")
    public   String  preSave(Book  book, Model model){
      if (book!=null && book.getBid()!=null && book.getBid()!=0) {
          Book b = bookBiz.selectByPrimaryKey(book.getBid());
          model.addAttribute("b",b);
      }
      return   "book/edit";

    }

}

3.2在BookMapper.xml文件编写查询的方法(并且实现)

  <select id="listPager" resultType="com.lz.model.Book" parameterType="com.lz.model.Book" >
    select
    <include refid="Base_Column_List" />
    from t_mvc_book
    <where>
      <if test="bname !=null">
      bname  like  concat ('%',#{bname},'%')
      </if>
    </where>
  </select>

3.3构建list界面（展示数据）

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8"%>
<%@ taglib uri="http://jsp.veryedu.cn" prefix="z"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <link
            href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
            rel="stylesheet">
    <script
            src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js"></script>
    <title>博客列表</title>
    <style type="text/css">
        .page-item input {
            padding: 0;
            width: 40px;
            height: 100%;
            text-align: center;
            margin: 0 6px;
        }

        .page-item input, .page-item b {
            line-height: 38px;
            float: left;
            font-weight: 400;
        }

        .page-item.go-input {
            margin: 0 10px;
        }
    </style>
</head>
<body>
<form class="form-inline"
      action="${pageContext.request.contextPath }/book/list" method="post">
    <div class="form-group mb-2">
        <input type="text" class="form-control-plaintext" name="bname"
               placeholder="请输入书籍名称">
        <!-- 			<input name="rows" value="20" type="hidden"> -->
        <!-- 不想分页 -->
     <%--   <input name="pagination" value="false" type="hidden">--%>
    </div>
    <button type="submit" class="btn btn-primary mb-2">查询</button>
    <a class="btn btn-primary mb-2" href="${pageContext.request.contextPath }/book/preSave">新增</a>
</form>

<table class="table table-striped">
    <thead>
    <tr>
        <th scope="col">书籍编号</th>
        <th scope="col">书籍名字</th>
        <th scope="col">书籍价格</th>
        <th scope="col">操作</th>
    </tr>
    </thead>
    <tbody>
    <c:forEach  var="b" items="${lst }">
        <tr>
            <td>${b.bid }</td>
            <td>${b.bname }</td>
            <td>${b.price }</td>
            <td>
                <a href="${pageContext.request.contextPath }/book/preSave?bid=${b.bid}">修改</a>
                <a href="${pageContext.request.contextPath }/book/del/${b.bid}">删除</a>
            </td>
        </tr>
    </c:forEach>
    </tbody>
</table>
<!-- 这一行代码就相当于前面分页需求前端的几十行了 -->
<z:page pageBean="${pageBean }"></z:page>
</body>
</html>

3.4构建edit界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
         pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>书籍编辑界面</title>
</head>
<body>
<form action="${pageContext.request.contextPath }/${empty b ? 'book/add' : 'book/edit'}" method="post">
    书籍编号:<input type="text" name="bid" value="${b.bid }"><br>
    书籍名字:<input type="text" name="bname" value="${b.bname }"><br>
    书籍价格:<input type="text" name="price" value="${b.price }"><br>
    <input type="submit">
</form>
</body>
</html>

3.5效果展示

1.增加

2.删除

3.修改

4.查询