1、留言板显示页面：note.php
<?php ???$host = "127.0.0.1";$user = "root";$pwd = "zst@123";$dbname = "php10";$db = new mysqli($host, $user, $pwd, $dbname);if($db->errno <> 0){ ???echo "数据库连接失败"; ???exit;}$sql = "select * from msg where id>15 order by id desc";$mysqli_result = $db->query($sql);if($mysqli_result == false){ ???echo "查询语句执行失败"; ???exit;}$rows = [];while($row = $mysqli_result->fetch_array(MYSQLI_ASSOC)){ ???$rows[] = $row;}//var_dump($rows);?><html> ???<head> ???????<meta charset="UTF-8"/> ???????<title>留言本</title> ???????<!--<link rel="stylesheet" type="text/css" href="test.css"> --> ???????<style type="text/css"> ???????????.wrap{ ???????????????width: 800px; ???????????????margin: 0px auto; ???????????} ???????????.add{ ???????????????overflow:hidden; ??<!--消除float--> ???????????} ???????????.add .content{ ???????????????width: 798px; ???????????????margin: 0px; ???????????????padding: 0px; ???????????} ???????????.add .user{ ???????????????float: left; ???????????} ???????????.add .btn{ ???????????????float: right; ???????????} ???????????.msg{ ???????????????margin: 20px 0px; ????????????????background: #ccc; ???????????????padding: 5px; ???????????} ???????????.msg .info{ ???????????????overflow: hidden; ???????????} ???????????.msg .user{ ???????????????float:left; ???????????????color: blue; ???????????} ???????????.msg .time{ ???????????????float: right; ???????????????color:999; ???????????} ???????????.msg .content{ ???????????????width: 100%; ???????????} ???????</style> ???</head> ???<body> ???????<div class="wrap"> ???????????<!--发表留言--> ???????????<div class="add"> ???????????????<form action="messageboard_class.php" method="post"> ???????????????????<textarea name="content" class="content" cols="50" rows="5"></textarea> ???????????????????<br/> ???????????????????<input name="user" class="user" type="text"/> ???????????????????<input class="btn" type="submit" value="发表留言"/> ???????????????</form> ???????????</div> ???????????<!--查看留言 --> ???????????<?php ???????????????//设置日期时区，否则会少7小时 ???????????????date_default_timezone_set("Asia/Shanghai"); ???????????????foreach ($rows as $key => $record) { ????????????????????????????????????> ???????????<div class="msg"> ???????????????<div class="info"> ???????????????????<span class="user"><?php echo $record["user"]; ?></span> ???????????????????<span class="time"><?php echo date(‘Y-m-d H:i:s‘, $record["intime"]); ?></span> ???????????????</div> ???????????????????<div class="content"> ???????????????????<?php echo $record["content"]; ?> ???????????????</div> ???????????</div> ???????????<?php ???????????????} ????????????> ???????</div> ???</body></html>2、提交留言后台处理：messageboard_class.php
<?phpinclude("messageboard_class_import.php"); ?//过滤留言名称的类include("connect.php"); ???????????????????//数据库连接工具类//var_dump($_POST);$content = $_POST[‘content‘];$user = $_POST[‘user‘];//使用包含文件中的类，初始化input类对象 $input = new input();if($input -> valid($content) == false){ ???die("输入的内容不能为空！"); ??//die方法：停止程序，在页面上显示内容}if($input -> valid($user) == false){ ???die("输入的用户名为空或不合法！");}//var_dump($_POST);/* 插入语句 *///设置日期时区，否则会少7小时date_default_timezone_set("Asia/Shanghai");$time = time();echo date("Y-m-d H:i:s", $time);$sql = "insert into msg(content, user, intime) values(‘{$content}‘, ‘{$user}‘, ‘{$time}‘)";$connectClass = new conClass();$db = $connectClass->getDB();$is = $db->query($sql);if($is == true){ ???echo "执行成功";}else{ ???echo "执行失败";}//重定向浏览器访问header("Location:note.php");/*//查询语句$sql = "select * from msg where id > 15 order by id desc";$con = new conClass();$db = $con -> getDB();$mysqli_result = $db ->query($sql);if($mysqli_result == false){ ???echo "SQL 错误"; ???exit;}//定义一个数组$rows = [];while($row = $mysqli_result->fetch_array(MYSQLI_ASSOC)){ ???$rows[] = $row; ??//rows 数组不写下标，意思是从0开始；}var_dump($rows); ?//可以看出是一个二维数组，键从0开始，值是每一行的数据（一维数组表示）*/?>过滤留言名称的类 messageboard_class_import.php
<?phpclass input{ ???public function valid($info){ ???????if($info == ""){ ???????????return false; ???????} ???????//禁止使用某个用户名留言 ???????$note = [‘张三‘, ‘李四‘, ‘王乐‘]; ???????foreach($note as $name => $value){ ???????????//echo $name; ???????????if($info == $value){ ???????????????return false; ???????????} ???????} ???????return true; ???}}?>数据库连接工具类connect.php
<?phpclass conClass{ ???//写入数据库 ???public function getDB(){ ???????$host = "127.0.0.1"; ???????$dbuser = "root"; ???????$passwd = "zst@123"; ???????$dbname = "php10"; ???????$db = new mysqli($host, $dbuser, $passwd, $dbname); ???????if($db->errno <> 0){ ???????????return null; ???????} ???????return $db; ???} ???}?>PHP基础知识总结（四） 留言板例子 ?知识应用
原文地址：https://www.cnblogs.com/wangle1001986/p/8644335.html