php使用cookie实现记住登录状态

一.检查用户是否登录

//检查用户是否登录 
function checklogin(){ 
if(empty($_SESSION['user_info'])){ //检查一下session是不是为空 
if(empty($_COOKIE['username']) || empty($_COOKIE['password'])){ //如果session为空，并且用户没有选择记录登录状 
header("location:login.php?req_url=".$_SERVER['REQUEST_URI']); //转到登录页面，记录请求的url，登录后跳转过去，用户体验好。 
}else{ //用户选择了记住登录状态 
$user = getUserInfo($_COOKIE['username'],$_COOKIE['password']); //去取用户的个人资料 
if(empty($user)){ //用户名密码不对没到取到信息，转到登录页面 
header("location:login.php?req_url=".$_SERVER['REQUEST_URI']); 
}else{ 
$_SESSION['user_info'] = $user; //用户名和密码对了，把用户的个人资料放到session里面 
} 
} 
} 
}

 

二，用户提交登录信息

username = trim($_POST['username']);  
$password = md5(trim($_POST['password']));  
$validatecode = $_POST['validateCode'];  
$ref_url = $_GET['req_url'];  
$remember = $_POST['remember'];  
  
$err_msg = '';  
if($validatecode!=$_SESSION['checksum']){  
$err_msg = "验证码不正确";  
}elseif($username=='' || $password==''){  
$err_msg = "用户名和密码都不能为空";  
}else{  
$row = getUserInfo($username,$password);  
  
if(empty($row)){  
$err_msg = "用户名和密码都不正确";  
}else{  
$_SESSION['user_info'] = $row;  
if(!empty($remember)){     //如果用户选择了，记录登录状态就把用户名和加了密的密码放到cookie里面  
setcookie("username", $username, time()+3600*24*365);  
setcookie("password", $password, time()+3600*24*365);  
}  
if(strpos($ref_url,"login.php") === false){  
header("location:".$ref_url);  
}else{  
header("location:main_user.php");  
}  
}  
}

 三，当用户点退出时，清出记录登录状态

//退出登录 
function logout(){  
unset($_SESSION['user_info']);  
if(!empty($_COOKIE['username']) || !empty($_COOKIE['password'])){  
setcookie("username", null, time()-3600*24*365);  
setcookie("password", null, time()-3600*24*365);  
}  
}

 四、简洁版实例

<?
//读取COOKIE的用户名和密码的值即可
if($_COOKIE['uname']!=''){$CKUNAME =  $_COOKIE['uname'];}
if($_COOKIE['pwd']!=''){$CKPWD =  $_COOKIE['pwd'];}
echo $CKUNAME;
echo '<br>';
echo $CKPWD;
?>
<form id="form1" name="form1" method="post" action="">
    <input type="text" name="uname" id="uname" value="<?=$CKUNAME;?>" /> <input
       type="password" name="pwd" id="pwd" value="<?=$CKPWD;?>" /> <input
       name="remember" type="checkbox" value="1" <? if($CKUNAME!=''){?>
       checked="checked" <? } ?> /> 记住我! <input type="submit" name="button"
       id="button" value="登录" />
</form>
<?
//登录，将用户名和密码存入到COOKIE
if($_POST['button']!=''){
    $uname = $_POST['uname'];
    $pwd = $_POST['pwd'];
    //如果输入的加密密码和COOKIE中不一样，那么就加密
    if($pwd!=$CKPWD){$pwd = md5($pwd);}
    $remember = $_POST['remember'];
    if($remember==1){
       setcookie("uname", $uname, time()+3600*24*30);
       setcookie("pwd", $pwd, time()+3600*24*30);
    }
}
?>