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phphtmldomevalsimple-html-dom

Using eval() to execute string of PHP that contains SimpleHTML

I'm trying to use eval() to execute a string of SimpleHTML. I'm fully aware of the dangers of eval() and will not be using any user input for the string that is to be executed.

$my_data = str_get_html('<html><body><a href=\"https://www.example.com\">Hello!</a></body></html>');

$str = '$my_data->find(\'a\', 0)->attr[\'href\']';

eval ("\$str = \"$str\";");

echo $str;

The above code doesn't execute, and after echoing $str, I get:

('a', 0)->attr['href']

What happened to the first part of the $str string (i.e. $my_data->find )? How can I actually execute the code from the $str string?

Solution

  • The code you are passing to the eval is wrong. You are trying to eval the following code:

    $str = "$my_data->find('a', 0)->attr['href']";

    The correct code would be: 

    $str = $my_data->find('a', 0)->attr['href'];

    Or:

    $str = "{$my_data->find('a', 0)->attr['href']}";

    This code works:

    <?php

require __DIR__ . '/simplehtmldom_1_9_1/simple_html_dom.php';

$my_data = str_get_html('<html><body><a href=\"https://www.example.com\">Hello!</a></body></html>');

$str = '$my_data->find(\'a\', 0)->attr[\'href\']';


eval ("\$str = $str;");

echo $str;