做一个小案例，主要复习一下mysqli面向过程，面向对象，PDO版本的基础SQL语句，也为自己复习做个参考。ok，本篇为mysqli面向过程篇（ procedure oriented programming => pop）
附上链接：
第一篇：php案例之后台数据显示-- mysqli面向过程版（procedure oriented programming => POP）
第二篇：php案例之后台数据显示-- mysqli面向对象版（Object Oriented Programming => OOP）
第三篇：php案例之后台数据显示-- PDO版（php data object）
做出来的效果如下,可能有点low，但是样式什么的自己搞吧：
先说一下大概思路吧
1，连接数据库2，数据展示，index页2.1，jsDom操组2.1.1，点击修改按钮出现下拉框2.1.2，复选框选择，全选、反选、全不选2.1.3，根据复选框进行多个数据同时操作注意点，直接在多选按钮两侧加form不行，要么会出现form提交混乱，要吗就不行解决，创建form元素，根据选中的多选框和form元素创建一个新的dom元素，然后js方式提交2.2,php2.2.1，根据搜索框有无和搜索内容显示页面内容2.2.2，增加一个用户2.2.3，根据用户id删除数据2.2.4，根据复选框同时删除数据2.2.5，根据用户id修改数据3，根据index页传入sql页面中进行操作
ok，开始了，目录展示
connect.php
<?php// 连接数据库$host= '127.0.0.1'; $user= 'root';$password = 'weicunbin123';$db = 'testguest';$conn =mysqli_connect($host,$user,$password,$db);if(mysqli_connect_error($conn)){//如果没有错误,会返回一个NULLdie("连接失败，错误:" . mysqli_connect_error($conn)); //打印错误信息}// 3,设置字符集mysqli_set_charset($conn,'utf8');?>
index.php
<?php// 连接数据库require dirname(__FILE__).'\connect.php';// 查。模糊查询// 判断是否点击查询语句，其实这里应该对查找到的数据进行操作，不过就图方便了if(isset($_GET['action']) && $_GET['action'] == 'search'){$clean = array();$clean['name'] =isset( $_POST['name']) ? $_POST['name'] : '';if( $clean['name'] == ' '){// 如果为空格的话，就默认为空了$clean['name'] = '';}$sql = "SELECT * FROM db_demo WHERE db_name LIKE '%{$clean['name']}%' ORDER BY db_date DESC";$dataResult = mysqli_query($conn,$sql);}else{$dataSql = "SELECT * FROM db_demo ORDER BY db_date DESC";$dataResult = mysqli_query($conn,$dataSql);}?><!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title><style>* {margin: 0; padding: 0;}body,html {padding: 10px;}table {border-collapse: collapse; width: 700px;}thead th {padding: 5px 10px;}tbody td {padding: 3px;}tr.show td, tr.hide td div {text-align: center;}tr.hide td .hidebox {overflow: hidden; height: 0;}tfoot tr {height: 40px; overflow: hidden;}</style></head><body><div class="adduser"><!-- 第一个表单，用于增加一个用户 --><form action="./sql.php?action=adduser" method="POST" name="add">添加：<input type="text" value="name" name = "name"><input type="text" value="password" name = "password"><input type="submit" value="确定提交"></form><br></div><div class="search"><!-- 搜索，按理说是用应该操作得到的数据，不过还有select语句，所以从数据库中返回数据 --><form action="./index.php?action=search" method="POST" name="search">搜索：<input type="text" name = "name" value = <?php echo isset( $clean['name']) ?$clean['name']: '' ?>><input type="submit" value="确认"></form><br></div><table border="1"><thead><tr><th></th><th>id</th><th>name</th><th>password</th><th>ctime</th><th>operation</th></tr></thead><tbody><?php// 将数据显示在页面上while($datalist = mysqli_fetch_assoc($dataResult)){?><tr class="show"><td><!-- 第二个表单控件，用于批量删除,有三个部分组成，这是第一个部分 --><input type="checkbox" name="select[]" value=<?php echo $datalist['db_id']; ?>></td><td> <?php echo $datalist['db_id']; ?></td><td> <?php echo $datalist['db_name'] ; ?></td><td> <?php echo $datalist['db_password'] ; ?></td><td> <?php echo $datalist['db_date']; ?></td><td><!-- 用于对当前用户修改显示或删除或修改操作 --><a href="javascript:void(0)" class="edit">修改</a><a href="./sql.php?action=del&id=<?php echo $datalist['db_id']; ?>">删除</a></td></tr><tr class="hide"><td colspan="6"><div class="hidebox"><!-- 第三个表单，用户修改当前用户信息 --><form action="./sql.php?action=edit&id=<?php echo $datalist['db_id']; ?>" method="POST" name="edit"><span>name： <input type="text" name="name" value=<?php echo $datalist['db_name'] ; ?> id=""></span><span>password: <input type="text" name="password" value=<?php echo $datalist['db_password'] ; ?> id=""></span><span><input type="submit" value="确认删除"></span></form></div></td></tr><?php } ?></tbody></table><div><label for="checkall" class="checkall"><input type="checkbox" id="checkall" value="全选"> <span>全选</span></label><label for="invertcheckall" class="invertcheckall"><input type="checkbox" id="invertcheckall"><span>反选</span></label><!-- 对应第二个表单控件，点击删除，这是第二个部分 --><button class="twosubmit">确认修改</button><!--对应第二个表单控件，组成一个form元素提交，这是第三个部分 --><div class="formbox" style="display:none"></div></div><script>// 批量删除提交var sectionDelete = (function(){// 点击确认修改document.querySelector('.twosubmit').onclick = function () {var opt = document.querySelectorAll('form[name="sectionDel"]');var input = document.querySelectorAll('input[ name="select[]"]'); var formbox = document.querySelector('.formbox'); var copyinput=''// 创建一个form元素var twoform = document.createElement("form")twoform.action = './sql.php?action=sectionDel';twoform.method="post";// 将选中的放入form中input.forEach(item => {if(item.checked == true){cloneinput = item.cloneNode();twoform.appendChild(cloneinput) }})// 放在页面上以提交formbox.appendChild(twoform) //提交到sql语句 twoform.submit()};})()// 下拉列表var dropdown = (function () {var oBtn = document.querySelectorAll('.show .edit');var hideBox = document.querySelectorAll('.hide .hidebox');var boxHeight = document.querySelectorAll('.hide form');oBtn.forEach((item, i) => {item.onclick = function () {hideBox.forEach((hide, n) => {hide.style.height = 0;hide.style.transition = "all 0.3s";if (i == n) {if (parseInt(window.getComputedStyle(hide).height) == 0) {hide.style.height = boxHeight[i].offsetHeight + 'px';}}})}})})()// 全选/全不选 反选var selopt = (function () {var checkall = document.querySelector('.checkall');var checkallInput = document.querySelector('.checkall input');var checkallTxt = document.querySelector('.checkall span');var invertcheckall = document.querySelector('.invertcheckall');var invertcheckallSpan = document.querySelector('.invertcheckall span');var newSel = new selectfn();checkall.onclick = checkallTxt.onclick = function () {checkallTxt.innerHTML == '全选' ? checkallTxt.innerHTML = '全不选' : checkallTxt.innerHTML = '全选'if (checkallInput.checked == false) {newSel.NotSelectAll();} else {newSel.selectAll();}}invertcheckall.onclick = invertcheckallSpan.onclick = function () {newSel.invertSelect();}// 全选/全不选 反选函数function selectfn() {var option = document.querySelectorAll('.show input[name="select[]"]');// 全选this.selectAll = function () {option.forEach(item => {item.checked = true;})}// 全不选this.NotSelectAll = function () {option.forEach(item => {item.checked = false;})}// 反选this.invertSelect = function () {option.forEach(item => {if (item.checked == true) {item.checked = false;} else {item.checked = true;}})}}})()</script></body></html>
sql.php
<?php// 连接数据库require dirname(__FILE__).'\connect.php';// 获取进行什么操组的关键字$action = $_GET['action'];switch($action){// 增加一个用户case 'adduser':$clean = array();$clean['name'] = $_POST['name'];$clean['password'] = $_POST['password'];$sql = "INSERT INTO db_demo(db_name,db_password,db_date) VALUES('{$clean['name']}','{$clean['password']}',NOW() )";// 执行语句和成功后的跳转语句query_location($sql) ;break;// 批量删除delete in，即全选，全不选，反选case 'sectionDel':$clean = array();$clean['select'] =isset($_POST['select']) ? check_live($_POST['select']):'';$sql = "DELETE FROM db_demo WHERE db_id in ({$clean['select']})";// 执行语句和成功后的跳转语句query_location($sql,'删除成功') ;break;// 点击删除case 'del': $clean = array();$clean['name'] = $_GET['id'];$sql = "DELETE FROM db_demo WHERE db_id = {$clean['name']}";// 执行语句和成功后的跳转语句query_location($sql,'删除成功') ;break;// 修改数据case 'edit':$clean = array();$clean['name'] = $_POST['name'];$clean['password'] = $_POST['password'];$clean['id'] = $_GET['id'];$sql = "UPDATE db_demo SET db_name='{$clean['name']}' ,db_password='{$clean['password']}' WHERE db_id = {$clean['id']}";// 执行语句和成功后的跳转语句query_location($sql,'修改成功','index.php','未修改数据或者出错','index.php') ;break;}// 封装的函数// 执行函数及执行成功后跳转的语句function query_location ($sql,$success='添加成功',$successhref = 'index.php',$error='添加成功',$errorhref = 'index.php'){global $conn;// 执行sql语句mysqli_query($conn,$sql);// 成功或失败后跳转if(mysqli_affected_rows($conn) > 0){echo "<script type='text/javascript'>alert('$success');window.location.href='$successhref'</script>";exit();}else{echo "<script type='text/javascript'>alert('$error');window.location.href='$errorhref'</script>";exit();}}// 将数组以 ‘，’隔开function check_live($arr = ''){$str = implode(',',$arr);return $str;}?>
