php include -如何使变量在包含的地方可用？

Question

我试图包括一个文件，这是刮我的所有数据从不同的网站，但它不工作。这是我的代码。

首先，抓取php文件。命名scrapedata.php

<?php

//Include the Simple HTML DOM to use its functions, used by other following scripts.
//navigate to the content of variable html and save it in price data variable
//get the whole html of the webpage into variable html
include 'simple_html_dom.php';
$html = file_get_html('http://www.play.com/Electronics/Electronics/4-/16230382/New-Apple-iPod-Touch-8GB-4th-Gen/Product.html?');
$price_data = $html->find('h6[id=bodycontent_0_middlecontent_1_ctl00_ctl00_product_ctl00__overview_ctl00__dataControl__price__headerSix',0)->plaintext; 


//Amazon.co.uk scrape
$amazon_html = file_get_html('http://www.amazon.co.uk/New-Apple-iPod-touch-Generation/dp/B0040GIZTI/ref=br_lf_m_1000333483_1_1_img?ie=UTF8&s=electronics&pf_rd_p=229345967&pf_rd_s=center-3&pf_rd_t=1401&pf_rd_i=1000333483&pf_rd_m=A3P5ROKL5A1OLE&pf_rd_r=1ZW9HJW2KN2C2MTRJH60');
$amazon_pd = $amazon_html->find('b[class=priceLarge]',0)->innertext;

libxml_use_internal_errors(true);

$dom = new DOMDocument();
$dom->loadHTML($amazon_html);

$xpath = new DOMXpath($dom);

$expr = "/html/body/div[@id='divsinglecolumnminwidth']/form[@id='handleBuy']/table[3]/tr[3]/td/div/span";
$nodes = $xpath->query($expr); // returns DOMNodeList object
// you can check length property i.e. $nodes->length

//echo $nodes->item(0)->nodeValue; // get first DOMNode object and its value
$stock_data = $nodes->item(0)->nodeValue;

if ( $stock_data == "In stock." ) {
    $stockyesno = "Yes";
} else {
    $stockyesno = "No";
}

//Currys scrape
$currys_html = file_get_html('http://www.currys.co.uk/gbuk/apple-new-ipod-touch-8gb-4th-generation-07677427-pdt.html');
$currys_pd = $currys_html->find('p[class=prd-amount]',0)->plaintext;
$currys_stk = $currys_html->find('/html/body/div/div/div[2]/div/div/div[2]/div/ul[2]/li/span')->plaintext;
//span[class=icon icon-check]',0);

echo $currys_stk;

if ( $currys_stk == "Available for home delivery" ) {
    $currys_stockyesno = "Yes";
} else {
    $currys_stockyesno = "No";
}

//Argos scrape
$argos_html = file_get_html('http://www.argos.co.uk/static/Product/partNumber/9282197/Trail/searchtext%3EIPOD+TOUCH.htm');
$argos_pd = $argos_html->find('span[class=actualprice]',0)->plaintext; 

//Ebuyer scrape
$ebuyer_html = file_get_html('http://www.ebuyer.com/product/237805');
$ebuyer_pd = $ebuyer_html->find('span[class=now]',0)->plaintext;

//PcWorld scrape
$pcworld_html = file_get_html('http://www.pcworld.co.uk/gbuk/apple-new-ipod-touch-8gb-4th-generation-07677427-pdt.html');
$pcworld_pd = $pcworld_html->find('p[class=prd-amount]',0)->plaintext; 
?>

然后是我的页面，它包含在其中，然后是访问包含文件中变量中的数据的页面。

<?php include 'scrapedata.php';?>     


   <!-- MYSQL DATABASE CODE -->
  <?php
$db_host = 'localhost';
$db_user = 'admin';
$db_pwd = '1admin';

$database = 'stock_checker';
$table = 'price_stock';

if (!mysql_connect($db_host, $db_user, $db_pwd))
    die("Can't connect to database");

if (!mysql_select_db($database))
    die("Can't select database");

?> 
<!-- MYSQL DATABASE CODE END-->

  //Insert the scraped data into the database.
mysql_query("INSERT INTO price_stock (retailer,price) VALUES('Play.com', '$play_pd' )") 
or die(mysql_error());
mysql_query("INSERT INTO price_stock (retailer,price,stock) VALUES('Amazon', '$amazon_pd', '$stockyesno' )") 
or die(mysql_error());
 mysql_query("INSERT INTO price_stock (retailer,price,stock) VALUES('Currys', '$currys_pd', '$currys_stk' )") 
or die(mysql_error());
mysql_query("INSERT INTO price_stock (retailer,price) VALUES('Argos', '$argos_pd' )") 
or die(mysql_error());
mysql_query("INSERT INTO price_stock (retailer,price) VALUES('eBuyer', '$ebuyer_pd' )") 
or die(mysql_error());
mysql_query("INSERT INTO price_stock (retailer,price) VALUES('PCWorld', '$pcworld_pd' )") 
or die(mysql_error());

?>

<!-- MYSQL DATABASE % TABLE CREATION CODE -->
<?php
// sending query
$result = mysql_query("SELECT * FROM {$table}");
if (!$result) {
    die("Query to show fields from table failed");
}

$fields_num = mysql_num_fields($result);


echo "<table width='650px'><tr>";

// printing table headers
for($i=0; $i<$fields_num; $i++)
{
    $field = mysql_fetch_field($result);
    echo "<td><b>{$field->name}</b></td>";
}
echo "</tr>\n";
// printing table rows
while($row = mysql_fetch_row($result))
{
    echo "<tr>";

    // $row is array... foreach( .. ) puts every element
    // of $row to $cell variable
    foreach($row as $cell)
        echo "<td>$cell</td>";

    echo "</tr>\n";
}
mysql_free_result($result);


?>

我做得对吗？我不知道是自动地包含它们，还是必须使它们成为全局的？

Answer 1

这是一个非常糟糕的想法。

您应该使用函数；传递和返回值。在脚本的开头包含文件，在需要时调用函数。不要将任何独立(非函数)代码放入所包含的文件中。

(顺便说一下，下一步是OOP和自动加载器。)

如果您想知道为什么这是一个非常糟糕的想法:我已经检查了您的代码5次(尽管没有深入分析)，仍然没有弄清楚您希望在两个文件之间共享哪些变量。如果我逐行查找，我会找到它，但我不想逐行查找。你也不需要，在3个月内，当你更新代码的时候。让我们的工作更轻松。

--

从一个角度来看，对象是函数和它们共享的状态的集合；所以这里是第三步: no functions ->一些functions -> functions分组在类中。我甚至不知道它是不是很好，但是PHP有this可以用来描述OOP。Autoloading是PHP用来按需加载类的机制，通常可以省去includes。

Answer 2

它们不需要显式导入。

试一下这个例子：

<?php
// a.php
$myVar = 123;

和

<?php
// b.php
include 'a.php'
echo isset($myVar)?'Included':'Not included';

与您发布的代码相关:我看不到您将数据添加到数据库的位置。你不是也应该这么做吗？

Answer 3

对这样的请求使用DOM解析不是一个好主意。亚马逊发布了一个简单的应用程序接口-在这里阅读：http://aws.amazon.com/de/