作为一名开发人员，我们经常需要对数据库中的数据进行增删改查（CRUD）操作。在本篇博客中，我们将重点介绍Lauiyi这个优秀的库是如何帮助我们简化和优化这些操作的。

Lauiyi是一个强大的开源工具，提供了丰富的函数和方法，可以轻松地实现对数据库的增删改查操作。下面让我们逐一介绍一下这些功能。

增加（Create）
在Lauiyi中，增加数据非常简单。我们只需使用add()或insert()函数，指定要添加的数据和目标表名，即可将数据插入到数据库中。例如：

python
from lauiyi import Lauiyi

创建Lauiyi对象

1.后台准备

1.dao方法

package com.zking.dao;import java.util.List;
import java.util.Map;import com.zking.entity.User;
import com.zking.util.BaseDao;
import com.zking.util.PageBean;
import com.zking.util.StringUtils;public class UserDao extends BaseDao<User> {public List<User> executeQuery(Class<User> clz, PageBean pageBean) throws Exception {String sql="select * from t_oa_user where 1=1 ";return super.executeQuery(sql, User.class, pageBean);
} public User login(User user) throws Exception {String sql="select * from t_oa_user  where loginName ='"+user.getLoginName()+"' and pwd = '"+user.getPwd()+"'";List<User> list = super.executeQuery(sql, User.class, null);if (list!=null&&list.size()==1) {return  list.get(0);}return null;
}public int registered(User user) throws Exception {String sql = "insert into t_oa_user(name,loginName,pwd,rid) values(?,?,?,?)";		return executeUpdate(sql, user,new String[] {"name","loginName","pwd","rid"});}public List<Map<String, Object>> userRole(User user, PageBean pageBean) throws Exception {String sql="SELECT\r\n" + "	u.*,\r\n" + "	(\r\n" + "CASE\r\n" + "	\r\n" + "	WHEN u.rid = '1' THEN\r\n" + "	'管理员' \r\n" + "	WHEN u.rid = '2' THEN\r\n" + "	'发起者' \r\n" + "	WHEN u.rid = '3' THEN\r\n" + "	'审批者' \r\n" + "	WHEN u.rid = '4' THEN\r\n" + "	'参与者' \r\n" + "	WHEN u.rid = '5' THEN\r\n" + "	'会议管理员' ELSE '其它' \r\n" + "END \r\n" + "	) rname \r\n" + "FROM\r\n" + "	`t_oa_user` u  where 1=1 ";String name=user.getName();if (StringUtils.isNotBlank(name)) {sql+=" and name like '%"+name+"%'";}return super.executeQuery(sql, pageBean);
} public int add(User user) throws Exception {String sql="insert into t_oa_user(name,loginName,pwd) values(?,?,?)";return super.executeUpdate(sql, user, new String[]{"name","loginName","pwd"});}public int del(User user) throws Exception {String sql="delete from where id = ?";return super.executeUpdate(sql, user, new String[]{"id"});}public int edit(User user) throws Exception {String sql="update t_oa_user set name = ?,loginName=?,pwd=? where id=?";return super.executeUpdate(sql, user, new String[]{"name","loginName","pwd" ,"id"});}public static void main(String[] args) throws Exception {User user = new User();
//	 user.setLoginName("ll");user.setName("朱");
//	 user.setPwd("789");
//	int add = new UserDao().add(user);
//	 List<Map<String, Object>> userRole = new UserDao().userRole(user, null);System.out.println(userRole);}
}

2.子实现类

package com.zking.web;import java.util.HashMap;
import java.util.List;
import java.util.Map;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.zking.dao.UserDao;
import com.zking.entity.User;
import com.zking.framework.ActionSupport;
import com.zking.framework.ModelDriver;
import com.zking.util.PageBean;
import com.zking.util.R;
import com.zking.util.ResponseUtil;public class Useraction extends ActionSupport implements ModelDriver<User> {
private User user=new User();
private UserDao userdao=new UserDao();public void login(HttpServletRequest req, HttpServletResponse resp) {try {User u = userdao.login(user);ResponseUtil.writeJson(resp, u);} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}public void registered(HttpServletRequest req, HttpServletResponse resp) {try {int n = userdao.registered(user);if(n>0) {ResponseUtil.writeJson(resp, n);}ResponseUtil.writeJson(resp, null);} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}public void userRole(HttpServletRequest req, HttpServletResponse resp) {try {PageBean pagebean=new PageBean();pagebean.setRequest(req);List<Map<String, Object>> userRole = userdao.userRole(user, pagebean);Map<String, Object>map=new HashMap<String, Object>();ResponseUtil.writeJson(resp, R.ok(0, "查询成功", pagebean.getTotal(),userRole) );} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}public void add(HttpServletRequest req, HttpServletResponse resp) throws Exception {int add = userdao.add(user);ResponseUtil.writeJson(resp, R.ok(0, "新增成功") );}public void del(HttpServletRequest req, HttpServletResponse resp) throws Exception {int del = userdao.del(user);ResponseUtil.writeJson(resp, R.ok(0, "删除成功") );}public void edit(HttpServletRequest req, HttpServletResponse resp) throws Exception {int edit = userdao.edit(user);ResponseUtil.writeJson(resp, R.ok(0, "修改成功") );}@Overridepublic User getModel() {// TODO Auto-generated method stubreturn user;}}

2.R工具类的使用

package com.zking.util;import java.util.HashMap;public class R extends HashMap{public R data(String key, Object value) {this.put(key, value);return this;}public static R ok(int code, String msg) {R r = new R();r.data("success", true).data("code", code).data("msg", msg);return r;}public static R error(int code, String msg) {R r = new R();r.data("success", false).data("code", code).data("msg", msg);return r;}public static R ok(int code, String msg,Object data) {R r = new R();r.data("success", true).data("code", code).data("msg", msg).data("data", data);return r;}public static R ok(int code, String msg, long count, Object data) {R r = new R();r.data("success", true).data("code", code).data("msg", msg).data("count", count).data("data", data);return r;}
}

3.查询前端代码实现

前端页面

<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%><%@ include file = "common/header.jsp" %><!DOCTYPE html >
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title></head>
<body>
<style type="text/css">
.layui-show{
height:100%;
}.layui-tab,
.layui-tab-content{height:100%;
}
</style><div class="layui-layout layui-layout-admin"><div class="layui-header"><div class="layui-logo layui-hide-xs layui-bg-black">layout demo</div><!-- 头部区域（可配合layui 已有的水平导航） --><ul class="layui-nav layui-layout-left"></ul><!-- 个人头像及账号操作 --><ul class="layui-nav layui-layout-right"><li class="layui-nav-item layui-hide layui-show-md-inline-block"><a href="javascript:;"><img src="//tva1.sinaimg.cn/crop.0.0.118.118.180/5db11ff4gw1e77d3nqrv8j203b03cweg.jpg" class="layui-nav-img">tester</a><dl class="layui-nav-child"><dd><a href="">Your Profile</a></dd><dd><a href="">Settings</a></dd><dd><a href="login.jsp">Sign out</a></dd></dl></li><li class="layui-nav-item" lay-header-event="menuRight" lay-unselect><a href="javascript:;"><i class="layui-icon layui-icon-more-vertical"></i></a></li></ul></div><div class="layui-side layui-bg-black"><div class="layui-side-scroll"><!-- 左侧导航区域（可配合layui已有的垂直导航） --><ul id="menu" class="layui-nav layui-nav-tree" lay-filter="menu"></ul></div></div><div class="layui-body"><!-- 内容主体区域 --><div style="padding: 15px;"><div class="layui-tab" lay-filter="demo" lay-allowclose="true"><ul class="layui-tab-title"><li class="layui-this" lay-id="11">网站设置</li><li lay-id="22">用户管理</li><li lay-id="33">权限分配</li><li lay-id="44">商品管理</li><li lay-id="55">订单管理</li></ul><div class="layui-tab-content" style=" height:600px" ><div class="layui-tab-item layui-show">内容1</div><div class="layui-tab-item">内容2</div><div class="layui-tab-item">内容3</div><div class="layui-tab-item">内容4</div><div class="layui-tab-item">内容5</div></div>
</div> </div></div><div class="layui-footer"><!-- 底部固定区域 -->底部固定区域</div>
</div>
<script src="static/index.js" ></script>
</body></html>

4.增删改实现

1.弹出层

<%@ 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>博客的编辑界面</title>
</head>
<body>
<form action="${pageContext.request.contextPath }/blog.action?methodName=${empty b ? 'add' : 'edit'}" method="post">
id:<input type="text" name="id" value="${b.id }"><br>
title:<input type="text" name="title" value="${b.title }"><br>
keyWord:<input type="text" name="keyWord" value="${b.keyWord }"><br>
<input type="submit">
</form>
</body>
</html>

2.浮层

<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%><%@include file="/common/header.jsp" %>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<%-- <script type="text/javascript" src="${pageContext.request.contextPath }/static/js/system/userEdit.js"></script>--%><title>用户新增</title>
</head>
<style>
.layui-form-select dl{max-height:150px;
}
</style>
<body>
<div style="padding:10px;"><form class="layui-form layui-form-pane" lay-filter="user"><input type="hidden" name="id"/><div class="layui-form-item"><label class="layui-form-label">用户名称</label><div class="layui-input-block"><input type="text" id="name" name="name" autocomplete="off" placeholder="请输入用户名" class="layui-input"></div></div><div class="layui-form-item"><label class="layui-form-label">用户角色</label><div class="layui-input-block"><select name="rid"><option value="">---请选择---</option><option value="1">管理员</option><option value="2">发起者</option><option value="3">审批者</option><option value="4">参与者</option><option value="5">会议管理员</option></select></div></div><div class="layui-form-item"><label class="layui-form-label">登录账号</label><div class="layui-input-block"><input type="text" name="loginName" lay-verify="required" placeholder="请输入账号" autocomplete="off" class="layui-input"></div></div><div class="layui-form-item"><label class="layui-form-label">登录密码</label><div class="layui-input-block"><input type="password" name="pwd" placeholder="请输入密码" autocomplete="off" class="layui-input"></div></div></form>
</div>
</body>
</html>

3分离的js代码

1.userManage.js

var table,$;var row;
layui.use(['table','jquery','layer'], function(){table = layui.tablelayer=layui.layer,$=layui.jquery;initTable();$("#btn_search").click(function(){query();});$("#btn_add").click(function(){row=null;edit('新增'); }); });function edit(title){layer.open({type: 2,                    //layer提供了5种层类型。可传入的值有：0（信息框，默认）1（页面层）2（iframe层）3（加载层）4（tips层）title:title,area: ['660px', '340px'],   //宽高skin: 'layui-layer-rim',    //样式类名content:  'jsp/system/userEdit.jsp', //书本编辑页面btn:['保存','关闭'],yes: function(index, layero){//调用子页面中提供的getData方法，快速获取子页面的form表单数据let data= $(layero).find("iframe")[0].contentWindow.getData();console.log(data);//判断title标题let methodName="add";if(title=="编辑")methodName="edit";$.post('user.action?methodName='+methodName,data,function(rs){if(rs.success){//关闭对话框layer.closeAll();//调用查询方法刷新数据query();}else{layer.msg(rs.msg,function(){});}},'json');},btn2: function(index, layero){layer.closeAll();}});}function query(){table.reload('test', {where: { //设定异步数据接口的额外参数，任意设name: $("#name").val()},page: {curr: 1 //重新从第 1 页开始}}); //只重载数
};function initTable(){table.render({elem: '#test',url:'user.action?methodName=userRole',toolbar: '#toolbarDemo' //开启头部工具栏，并为其绑定左侧模板,defaultToolbar: ['filter', 'exports', 'print', { //自定义头部工具栏右侧图标。如无需自定义，去除该参数即可title: '提示',layEvent: 'LAYTABLE_TIPS',icon: 'layui-icon-tips'}],title: '用户数据表',cols: [[{type: 'checkbox', fixed: 'left'},{field:'id', title:'ID', width:80, fixed: 'left', unresize: true, sort: true},{field:'loginName', title:'账户名', width:120, edit: 'text'},{field:'name', title:'用户名', width:150, edit: 'text', templet: function(res){return '<em>'+ res.name +'</em>'}},{field:'pwd', title:'密码', width:80, edit: 'text', sort: true},{field:'rname', title:'角色名', width:100},{field:'right', title:'签名'}]],page: true});//头工具栏事件//监听行工具事件table.on('tool(test)', function(obj){var row = obj.data;//console.log(obj)if(obj.event === 'del'){layer.confirm('确认删除吗?', {icon: 3, title:'提示'}, function(index){$.post('user.action',{'methodName':'del','id':row.id},function(rs){if(rs.success){//调用查询方法刷新数据query();}else{layer.msg(rs.msg,function(){});}},'json');layer.close(index);});} else if(obj.event === 'edit'){edit("编辑");}});
}

2.userEdit.js

let layer,form,$;
layui.use(['layer','form','jquery'],function(){layer=layui.layer,form=layui.form,$=layui.jquery;initData();
});function initData(){console.log(parent.row);if(null!=parent.row){//因为layui.each内部的逻辑问题导致的所以要先深拷贝一份然后再去val//parent.row：表格行对象form.val('user',$.extend({}, parent.row||{}));$('#name').attr('readonly','readonly');}
}function getData(){return form.val('user');
}

3.index.js

var element,layer,util,$;layui.use(['element', 'layer', 'util'], function(){element = layui.element,layer = layui.layer,util = layui.util,$ = layui.$$.ajax({url:"{pageContext.request.contextPath}/permisson.action?methodName=menus",dataType:'json',success:function(data){console.log(data);	 var htmlStr ='';$.each(data,function(i,n){htmlStr+='<li class="layui-nav-item layui-nav-itemed">';htmlStr+='<a class="" href="javascript:;">'+n.text+'</a>';if (n.hasChildren) {var children=n.children;htmlStr+=' <dl class="layui-nav-child">';$.each(children,function(idx,node){htmlStr+=' <dd><a href="javascript:;" onclick="openTab(\''+node.text+'\',\''+node.attributes.self.url+'\',\''+node.id +'\')">'+node.text+'</a></dd>';console.log(node.text);	 });htmlStr+=' </dl>';}htmlStr+='</li>'; console.log(n.text);	 });$("#menu").html(htmlStr);element.render('menu');}});});
/*** */
function openTab(title,content,id) {var $node=$('li[lay-id="'+id+'"]')console.log($node);if ($node.length==0) {element.tabAdd('demo', {title: title,content: "<iframe frameborder='0' src='"+content+"' scrolling='auto' style='width:100%;height:100%;'></iframe>",id: id //实际使用一般是规定好的id，这里以时间戳模拟下})}}

5.运行效果