login.html<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" ""><html xmlns=""><head><meta http-equiv="Content-Type" content="text/html; charset=gbk" /><title>用户登录</title><style type="text/css">html{font-size:12px;}fieldset{width:520px; margin: 0 auto;}legend{font-weight:bold; font-size:14px;}label{float:left; width:70px; margin-left:10px;}.left{margin-left:80px;}.input{width:150px;}span{color: #666666;}</style><script language=JavaScript><!–function InputCheck(LoginForm){ if (LoginForm.username.value == "") {alert("请输入用户名!");LoginForm.username.focus();return (false); } if (LoginForm.password.value == "") {alert("请输入密码!");LoginForm.password.focus();return (false); }}//–></script></head><body><div><fieldset><legend>用户登录</legend><form name="LoginForm" method="post" action="login.php" onSubmit="return InputCheck(this)"><p><label for="username" class="label">用户名:</label><input id="username" name="username" type="text" class="input" /><p/><p><label for="password" class="label">密 码:</label><input id="password" name="password" type="password" class="input" /><p/><p><input type="submit" name="submit" value=" 确 定 " class="left" /></p></form></fieldset></div></body></html>conn.php<?php/******************************数据库连接*****************************/$conn = @mysql_connect("localhost","root","root123");if (!$conn){die("连接数据库失败：" . mysql_error());}mysql_select_db("test", $conn);//字符转换，读库mysql_query("set character set ‘gbk’");//写库mysql_query("set names ‘gbk’");?>reg.php<?phpif(!isset($_POST[‘submit’])){exit(‘非法访问!’);}$username = $_POST[‘username’];$password = $_POST[‘password’];$email = $_POST[’email’];//注册信息判断if(!preg_match(‘/^[\w\x80-\xff]{3,15}$/’, $username)){exit(‘错误：用户名不符合规定。<a href="javascript:history.back(-1);">返回</a>’);}if(strlen($password) < 6){exit(‘错误：密码长度不符合规定。<a href="javascript:history.back(-1);">返回</a>’);}if(!preg_match(‘/^w+([-+.]w+)*@w+([-.]w+)*.w+([-.]w+)*$/’, $email)){exit(‘错误：电子邮箱格式错误。<a href="javascript:history.back(-1);">返回</a>’);}//包含数据库连接文件include(‘conn.php’);//检测用户名是否已经存在$check_query = mysql_query("select uid from user where username=’$username’ limit 1");if(mysql_fetch_array($check_query)){echo ‘错误：用户名 ‘,$username,’ 已存在。<a href="javascript:history.back(-1);">返回</a>’;exit;}//写入数据$password = MD5($password);$regdate = time();$sql = "INSERT INTO user(username,password,email,regdate)VALUES(‘$username’,’$password’,’$email’,$regdate)";if(mysql_query($sql,$conn)){exit(‘用户注册成功！点击此处 <a href="login.html">登录</a>’);} else {echo ‘抱歉！添加数据失败：’,mysql_error(),'<br />’;echo ‘点击此处 <a href="javascript:history.back(-1);">返回</a> 重试’;}?>login.html<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" ""><html xmlns=""><head><meta http-equiv="Content-Type" content="text/html; charset=gbk" /><title>用户登录</title><style type="text/css">html{font-size:12px;}fieldset{width:300px; margin: 0 auto;}legend{font-weight:bold; font-size:14px;}.label{float:left; width:70px; margin-left:10px;}.left{margin-left:80px;}.input{width:150px;}span{color: #666666;}</style><script language=JavaScript><!–function InputCheck(LoginForm){ if (LoginForm.username.value == "") {alert("请输入用户名!");LoginForm.username.focus();return (false); } if (LoginForm.password.value == "") {alert("请输入密码!");LoginForm.password.focus();return (false); }}//–></script></head><body><div><fieldset><legend>用户登录</legend><form name="LoginForm" method="post" action="login.php" onSubmit="return InputCheck(this)"><p><label for="username" class="label">用户名:</label><input id="username" name="username" type="text" class="input" /><p/><p><label for="password" class="label">密 码:</label><input id="password" name="password" type="password" class="input" /><p/><p><input type="submit" name="submit" value=" 确 定 " class="left" /></p></form></fieldset></div></body></html>login.php<?phpsession_start();//注销登录if($_GET[‘action’] == "logout"){unset($_SESSION[‘userid’]);unset($_SESSION[‘username’]);echo ‘注销登录成功！点击此处 <a href="login.html">登录</a>’;exit;}//登录if(!isset($_POST[‘submit’])){exit(‘非法访问!’);}$username = htmlspecialchars($_POST[‘username’]);$password = MD5($_POST[‘password’]);//包含数据库连接文件include(‘conn.php’);//检测用户名及密码是否正确$check_query = mysql_query("select uid from user where username=’$username’ and password=’$password’ limit 1");if($result = mysql_fetch_array($check_query)){//登录成功$_SESSION[‘username’] = $username;$_SESSION[‘userid’] = $result[‘uid’];echo $username,’ 欢迎你！进入 <a href="my.php">用户中心</a><br />’;echo ‘点击此处 <a href="login.php?action=logout">注销</a> 登录！<br />’;exit;} else {exit(‘登录失败！点击此处 <a href="javascript:history.back(-1);">返回</a> 重试’);}?>my.php<?phpsession_start();//检测是否登录，，若没登录则转向登录界面if(!isset($_SESSION[‘userid’])){header("Location:login.html");exit();}//包含数据库连接文件include(‘conn.php’);$userid = $_SESSION[‘userid’];$username = $_SESSION[‘username’];$user_query = mysql_query("select * from user where uid=$userid limit 1");$row = mysql_fetch_array($user_query);echo ‘用户信息：<br />’;echo ‘用户ID：’,$userid,'<br />’;echo ‘用户名：’,$username,'<br />’;echo ‘邮箱：’,$row[’email’],'<br />’;echo ‘注册日期：’,date("Y-m-d", $row[‘regdate’]),'<br />’;echo ‘<a href="login.php?action=logout">注销</a> 登录<br />’;?>
艰苦能磨练人的意志。
