8-2 function.php

<?php
// error_reporting(0);

//連線到資料庫
function link_db()
{
    $db = new mysqli(_DB_HOST, _DB_USER, _DB_PASS, _DB_NAME);
    if ($db->connect_error) {
        die('無法連上資料庫：' . $db->connect_error);
    }
    $db->set_charset("utf8");
    return $db;
}

//讀出單一文章
function show_article($sn)
{
    global $db, $smarty;

    require_once 'HTMLPurifier/HTMLPurifier.auto.php';
    $config   = HTMLPurifier_Config::createDefault();
    $purifier = new HTMLPurifier($config);

    //目前文章
    $sql             = "SELECT * FROM `article` WHERE `sn`='$sn'";
    $result          = $db->query($sql) or die($db->error);
    $data            = $result->fetch_assoc();
    $data['content'] = $purifier->purify($data['content']);

    //下一篇文章
    $sql             = "SELECT * FROM `article` WHERE `update_time` < '{$data['update_time']}' ORDER BY `update_time` DESC LIMIT 0,1";
    $result          = $db->query($sql) or die($db->error);
    $next            = $result->fetch_assoc();
    $next['content'] = $purifier->purify($next['content']);

    //上篇文章
    $sql             = "SELECT * FROM `article` WHERE `update_time` > '{$data['update_time']}' ORDER BY `update_time` LIMIT 0,1";
    $result          = $db->query($sql) or die($db->error);
    $prev            = $result->fetch_assoc();
    $prev['content'] = $purifier->purify($prev['content']);

    $smarty->assign('article', $data);
    $smarty->assign('next', $next);
    $smarty->assign('prev', $prev);

}