ผมทำอะไรผิด งงไปหมดแล้ว [PHP]

สรุปรวมเลยนะครับ
ไฟล์ class-database.php ถ้าไม่คอมเม้นบรรทัดนี้ //require_once 'class-tool.php'; ไว้จะขึ้นแบบนี้ครับ
Parse error: syntax error, unexpected T_CONSTANT_ENCAPSED_STRING in /home/com12317/public_html/nongfang/class-database.php on line 1

โค๊ด:

<?php

//require_once &#39;class-tool.php&#39;;

class database_app {    

    private $tool;

    private $config;

    private $link;



    public function __construct(){

        $this->tool = new tool_app();

        $this->config = $this->tool->request_config();

        $this->connect_database();

    }



    public function connect_database(){

        $this->link = mysql_connect($this->config[&#39;db&#39;][&#39;host&#39;], $this->config[&#39;db&#39;][&#39;user&#39;], $this->config[&#39;db&#39;][&#39;pass&#39;]);

        mysql_query("USE {$this->config[&#39;db&#39;][&#39;name&#39;]}", $this->link);

        mysql_query("SET NAMES utf8", $this->link);

    }

}
?>

ไฟล์ auto-config.php จะขึ้น error แบบนี้ครับ
Fatal error: Class 'database_app' not found in /home/com12317/public_html/nongfang/auto-config.php on line 8

โค๊ด:

<?php
set_time_limit(0);

require_once &#39;class-tool.php&#39;;
$tool = new tool_app();

require_once &#39;class-database.php&#39;;
$database = new database_app();

$wp = $database->wordpress_config();
$tool->display_array($wp);

if($wp != false){
    require_once &#39;class-wordpress.php&#39;;
    $wordpress = new wordpress_app("http://www.{$wp[&#39;w_url&#39;]}/");

    $writing = $wordpress->writing_setting();
    $return_data[] = $writing;

    $delete_post = $wordpress->delete_post();
    $return_data[] = $delete_post;

    $delete_page = $wordpress->delete_page();
    $return_data[] = $delete_page;

    $add_category = $wordpress->create_category();
    $category_count = (int)count($add_category);
    for($c = 0; $c < $category_count; $c++){
        $return_data[] = $add_category[$c];
    }

    $delete_link = $wordpress->delete_link();
    $link_count = (int)count($delete_link);
    for($a = 0; $a < $link_count; $a++){
        $return_data[] = $delete_link[$a];
    }

    $general = $wordpress->general_setting($wp[&#39;w_url&#39;], &#39;Dofollow Social Bookmarking Sites. Get One Way Backlinks.&#39;);
    $return_data[] = $general;

    $discussion = $wordpress->discussion_setting();
    $return_data[] = $discussion;

    $permalink = $wordpress->permalink_setting();
    $return_data[] = $permalink;

    $plugin = $wordpress->activate_plugin();
    $plugin_count = (int)count($plugin);
    for($b = 0; $b < $plugin_count; $b++){
        $return_data[] = $plugin[$b];
    }

    $seo = $wordpress->seo_setting($wp[&#39;w_url&#39;], &#39;Dofollow Social Bookmarking Sites. Get One Way Backlinks.&#39;, &#39;dofollow, social, bookmarking, sites, get, one, way, backlinks&#39;);
    $return_data[] = $seo;

    $sitemap = $wordpress->sitemap_setting();
    $return_data[] = $sitemap;
}

?>

<?php
set_time_limit(0);

require_once 'class-tool.php';
$tool = new tool_app();

require_once('class-database.php');
$db = new database_app();

$wp = $database->wordpress_config();
$tool->display_array($wp);

if($wp != false){
    require_once 'class-wordpress.php';
    $wordpress = new wordpress_app("http://www.{$wp['w_url']}/");

    $writing = $wordpress->writing_setting();
    $return_data[] = $writing;

    $delete_post = $wordpress->delete_post();
    $return_data[] = $delete_post;

    $delete_page = $wordpress->delete_page();
    $return_data[] = $delete_page;

    $add_category = $wordpress->create_category();
    $category_count = (int)count($add_category);
    for($c = 0; $c < $category_count; $c++){
        $return_data[] = $add_category[$c];
    }

    $delete_link = $wordpress->delete_link();
    $link_count = (int)count($delete_link);
    for($a = 0; $a < $link_count; $a++){
        $return_data[] = $delete_link[$a];
    }

    $general = $wordpress->general_setting($wp['w_url'], 'Dofollow Social Bookmarking Sites. Get One Way Backlinks.');
    $return_data[] = $general;

    $discussion = $wordpress->discussion_setting();
    $return_data[] = $discussion;

    $permalink = $wordpress->permalink_setting();
    $return_data[] = $permalink;

    $plugin = $wordpress->activate_plugin();
    $plugin_count = (int)count($plugin);
    for($b = 0; $b < $plugin_count; $b++){
        $return_data[] = $plugin[$b];
    }

    $seo = $wordpress->seo_setting($wp['w_url'], 'Dofollow Social Bookmarking Sites. Get One Way Backlinks.', 'dofollow, social, bookmarking, sites, get, one, way, backlinks');
    $return_data[] = $seo;

    $sitemap = $wordpress->sitemap_setting();
    $return_data[] = $sitemap;
}

?>

<?php

require_once 'class-tool.php';

class database_app {

    private $tool;

    private $config;

    private $link;

    public function __construct(){

        $this->tool = new tool_app();

        $this->config = $this->tool->request_config();

        $this->connect_database();

    }

    public function connect_database(){

        $this->link = mysql_connect($this->config['db']['host'], $this->config['db']['user'], $this->config['db']['pass']);

        mysql_query("USE {$this->config['db']['name']}", $this->link);

        mysql_query("SET NAMES utf8", $this->link);

    }

}
?>