保存在数据库中的PHP CODE需要运行

Question

I have the blow code saved in database

<script type="text/javascript" src="$url/js/jquery-ui.min.js"></script>
<script type="text/javascript" src="$url/js/ui.selectmenu.js"></script>

I want to fetch this code from database and then assign it to a variable and then I want to use $url which is defined above in my code in file.

So here is the scenario

$url is defined in file example.php foreg $url = 'http://localhost';

fetch a piece of code from database (the code above)

assign it to a variable foreg $content = (code fetch from mysql is here)

and in the end $content should contain

<script type="text/javascript" src="http://localhost/js/jquery-ui.min.js"></script>
<script type="text/javascript" src="http://localhost/js/ui.selectmenu.js"></script>

This code is just an example code and I have totally different code but scenario is kinda same. Anyone can please help.

PS And my code could contain url() (a custom function I created in another file.)

Answer 1

$content = str_replace('$url', 'http://localhost', $content);

Answer 2

You could do something like this:

$result = mysql_query("SELECT code FROM MyCodeTable WHERE MyColumn = 'something'");

if ($result && mysql_num_rows($result) > 0) {
    $row = mysql_fetch_object($result);

    $content = str_replace('$url', $url, $row->code);
}

Notes: Ideally you wouldn't fetch your data from MySQL like this, but use another method like PDO instead. Also, like Seagull illustrated in his example, using str_replace is a safer way to do this rather than eval because you should not trust the data you store in your database.