php用户登录代码

$admin_name="admin";
$admin_pawd="admin";
if($php_auth_user!=$admin_name||$php_auth_pw!=$admin_pawd)
{
header('www-authenticate: basic realm="系统验证"');
header('http/1.0 401 unauthorized');
echo "服务器拒绝请求,你没有权限!";
exit();
}

//

if (empty($_server['php_auth_user'])) {
header("content-type: text/html; charset=big5");
header('www-authenticate: basic realm=" authentication "');
header('http/1.0 401 unauthorized');
echo '请输入正确的账号及密码, 不可以取消!';
exit;
} else {
echo "你登录的账号是 ".$_server['php_auth_user']."
";
echo "你使用的密码是 ".$_server['php_auth_pw']."

";
$correctname="john";
$correctpwd="1234" ;
if (($_server['php_auth_user'] != $correctname) or
($_server['php_auth_pw'] !=$correctpwd)){
echo "登录失败, 请打开新的浏览器重新登录";
}else{
echo "登录成功.....";
}
}
?>

if (($_post['name'] != "john") or ($_post['passwd'] != "1234")):
?>

";
echo "你登录的账号是 ".$_post['name']."
";
echo "你使用的密码是 ".$_post['passwd'];
endif
?>