php在使用SimpleHTMLDOM渲染之前抓取页面的内容

Question

OK, the title is vague but i just dont know how to word this.

what I want to do is parse the entire page before rendering, then select a certain div from the page using Simple HTML DOM PHP and render that instead of the entire page, if the header of the page matches through if(isset($_SERVER[] call

Trouble is, i dont know how to do it, i cant select the current page using PHP (using $_SERVER[]?). I dont even know if I'm making sense.

say we start with how the external library works:

$html = file_get_html(''); // Get HTML of this page.. somehow
$div = $html->find('div[id=mainContent]'); // or 'div#mainContent'

But how do I echo the contents of that div? and will this render the page first?

Can anyone help me?

Answer 1

You can obtain this in a cleaner way using, as suggested, ob_get_contents. With appropriate use of core PHP directives and inclusion, you can make it so you don't have to touch the existing PHP files at all!

<?php
    // This goes before the page, and this can be done automatically (i.e. without
    // modifying the existing PHP file) using auto prepend:
    // http://www.php.net/manual/en/ini.core.php#ini.auto-prepend-file
    ob_start();
?>

// The "old" page ...

<?php
    // This goes after the page, and again can be done automatically using
    // auto append (see above).
    // This 'if' can also check whether this page is one of those that must be
    // manipulated, or not.
    if(!isset($_SERVER['EXAMPLE_HEADER']) || ('false'==$_SERVER['EXAMPLE_HEADER']))
    {
        $html = ob_get_clean();

        // Include is only necessary in this scope -- full path may be needed, though
        include_once('simple_html_dom.php');

        // Here, $html is parsed to yield a DOM object
        // ...

        foreach($dom->find('div[id=mainContent]') as $div)
        {
            echo $div->innertext;
        }
?>