<html>
<head>
<title>Login</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head>
<body>
<form name="form1" method="post" action="login.php">
<table width="300" border="0" align="center" cellpadding="2" cellspacing="2">
<tr>
<td width="150"><div align="right">用户名:</div></td>
<td width="150"><input type="text" name="username"></td>
</tr>
<tr>
<td><div align="right">密码:</div></td>
<td><input type="password" name="passcode"></td>
</tr>
<tr>
<td><div align="right">Cookie保存时间:</div></td>
<td><select name="cookie" id="cookie">
<option value="0" selected>浏览器进程</option>
<option value="1">保存1天</option>
<option value="2">保存30天</option>
<option value="3">保存365天</option>
</select></td>
</tr>
</table>
<p align="center">
<input type="submit" name="Submit" value="Submit">
<input type="reset" name="Reset" value="Reset">
</p>
</form>
</body>
</html>
-------------------------------------------------------------------------------------------------------------------------
<?php
@mysql_connect("localhost", "root","1981427") //选择数据库之前需要先连接数据库服务器
or die("数据库服务器连接失败");
@mysql_select_db("test") //选择数据库mydb
or die("数据库不存在或不可用");
//获取用户输入
$username = $_POST['username'];
$passcode = $_POST['passcode'];
//执行SQL语句获得Session的值
$query = @mysql_query("select username, userflag from users "
."where username = '$username' and passcode = '$passcode'")
or die("SQL语句执行失败");
//判断用户是否存在,密码是否正确
if($row = mysql_fetch_array($query))
{
session_start(); //标志Session的开始
//判断用户的权限信息是否有效,如果为1或0则说明有效
if($row['userflag'] == 1 or $row['userflag'] == 0)
{
$_SESSION['username'] = $row['username'];
$_SESSION['userflag'] = $row['userflag'];
echo "<a href="main.php" mce_href="main.php">欢迎登录,点击此处进入欢迎界面</a>";
}
else //如果权限信息无效输出错误信息
{
echo "用户权限信息不正确";
}
}
else //如果用户名和密码不正确,则输出错误
{
echo "用户名或密码错误";
}
?>
-------------------------------------------------------------------------------------------------------------------------
<?php
session_start();
unset($_SESSION['username']);
unset($_SESSION['passcode']);
unset($_SESSION['userflag']);
// 最后彻底销毁session.
session_destroy();
echo "注销成功";
?>
<?php
// 初始化session.
session_start();
/*** 删除所有的session变量..也可用unset($_SESSION[xxx])逐个删除。****/
$_SESSION = array();
/***删除sessin id.由于session默认是基于cookie的,所以使用setcookie删除包含session id的cookie.***/
if (isset($_COOKIE[session_name()])) {
setcookie(session_name(), '', time()-42000, '/');
}
// 最后彻底销毁session.
session_destroy();
?>
由此我们可以得出删除Session的步骤:
①session_start()
②$_SESSION=array()/unset($_SESSION['xxx'])
③session_destroy()
-------------------------------------------------------------------------------------------------------------------------
<?php
session_start();
if(isset($_SESSION['username']))
{
@mysql_connect("localhost", "root","1981427") //选择数据库之前需要先连接数据库服务器
or die("数据库服务器连接失败");
@mysql_select_db("test") //选择数据库mydb
or die("数据库不存在或不可用");
//获取Session
$username = $_SESSION['username'];
//执行SQL语句获得userflag的值
$query = @mysql_query("select userflag from users "
."where username = '$username'")
or die("SQL语句执行失败");
$row = mysql_fetch_array($query);
//判断当前数据库中的权限信息与Session中的信息比较,如果不同则更新Session的信息
if($row['userflag'] != $_SESSION['userflag'])
{
$_SESSION['userflag'] = $row['userflag'];
}
//根据Session的值输出不同的欢迎信息
if($_SESSION['userflag'] == 1)
echo "欢迎管理员".$_SESSION['username']."登录系统";
if($_SESSION['userflag'] == 0)
echo "欢迎用户".$_SESSION['username']."登录系统";
echo "<a href="logout.php" mce_href="logout.php">注销</a>";
}
else
{
echo "您没有权限访问本页面";
}
?>
-------------------------------------------------------------------------------------------------------------------------
-------------------------------------------------------------cookie登录验证实例---------------------------------------------
<html>
<head>
<title>Login</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head>
<body>
<form name="form1" method="post" action="login.php">
<table width="300" border="0" align="center" cellpadding="2" cellspacing="2">
<tr>
<td width="150"><div align="right">用户名:</div></td>
<td width="150"><input type="text" name="username"></td>
</tr>
<tr>
<td><div align="right">密码:</div></td>
<td><input type="password" name="passcode"></td>
</tr>
<tr>
<td><div align="right">Cookie保存时间:</div></td>
<td><select name="cookie" id="cookie">
<option value="0" selected>浏览器进程</option>
<option value="1">保存1天</option>
<option value="2">保存30天</option>
<option value="3">保存365天</option>
</select></td>
</tr>
</table>
<p align="center">
<input type="submit" name="Submit" value="Submit">
<input type="reset" name="Reset" value="Reset">
</p>
</form>
</body>
</html>
-------------------------------------------------------------------------------------------------------------------------
<?php
@mysql_connect("localhost", "root","1981427") //选择数据库之前需要先连接数据库服务器
or die("数据库服务器连接失败");
@mysql_select_db("test") //选择数据库mydb
or die("数据库不存在或不可用");
//获取用户输入
$username = $_POST['username'];
$passcode = $_POST['passcode'];
$cookie = $_POST['cookie'];
//执行SQL语句
$query = @mysql_query("select username, userflag from users "
."where username = '$username' and passcode = '$passcode'")
or die("SQL语句执行失败");
//判断用户是否存在,密码是否正确
if($row = mysql_fetch_array($query))
{
if($row['userflag'] == 1 or $row['userflag'] == 0) //判断用户权限信息是否有效
{
switch($cookie) //根据用户的选择设置cookie保存时间
{
case 0: //保存Cookie为浏览器进程
setcookie("username", $row['username']);
break;
case 1: //保存1天
setcookie("username", $row['username'], time()+24*60*60);
break;
case 2: //保存30天
setcookie("username", $row['username'], time()+30*24*60*60);
break;
case 3: //保存365天
setcookie("username", $row['username'], time()+365*24*60*60);
break;
}
header("location: main.php"); //自动跳转到main.php
}
else
{
echo "用户权限信息不正确";
}
}
else
{
echo "用户名或密码错误";
}
?>
-------------------------------------------------------------------------------------------------------------------------
<?php
session_start();
if(isset($_COOKIE['username']))
{
@mysql_connect("localhost", "root","1981427") //选择数据库之前需要先连接数据库服务器
or die("数据库服务器连接失败");
@mysql_select_db("test") //选择数据库mydb
or die("数据库不存在或不可用");
//获取Session
$username = $_COOKIE['username'];
//执行SQL语句获得userflag的值
$query = @mysql_query("select userflag from users "
."where username = '$username'")
or die("SQL语句执行失败");
$row = mysql_fetch_array($query);
//获得用户权限信息
$flag = $row['userflag'];
//根据userflag的值输出不同的欢迎信息
if($flag == 1)
echo "欢迎管理员".$_COOKIE['username']."登录系统";
if($flag == 0)
echo "欢迎用户".$_COOKIE['username']."登录系统";
echo "<a href="logout.php" mce_href="logout.php">注销</a>";
}
else
{
echo "您没有权限访问本页面";
}
?>
-------------------------------------------------------------------------------------------------------------------------
<?php
setcookie("username");
echo "注销成功";
?>
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