Run PHP coming into a mySQL result - php

Question

This is maybe about the 4 time I ask this question all over the web without having a working solution.
It is driving me crazy.
I will try to make it as easier as possible to understand.
I have some code inside a database table, that looks like this:
<div> Hello my name is {$name}</div>
<span> I come from {$city}</span>
<div>I am {$age} years old</div>
I repeat, this text come from a mySQL table that I SELECT with the following code:
function getPageContent($page) {
$q='SELECT * FROM pages WHERE Page="'.$page.'"';
$r=mysql_query($q) or die(mysql_error());
while($row = mysql_fetch_array($r)) {
$content= $row['Content'];
}
return $content;
}
As you may see there are some PHP variables in the above code, such as {$age} or {$city}, they are only samples because I won't know the exact content.
What I need to do is to find a way for PHP to get the contents of the $content variable ( string coming from the DB SELECT ), to recognize the variables inside the brackets {$foo} as normal PHP variables and to run them before echoing the final code.
As you may see the $content variable may have different and unknown variables inside it, so I must find a way to get those variables whatever they represent.
I do not know if the right thing to use here is eval(). But seems that eval() works only with something like {echo 'value'} and not with variables {$foo}, or {echo $foo} because variables won't be recognized at all.
Does anyone have a solution for this?
This is driving me crazy.
The concept is to give to the users the possibility to enter HTML text inside my mySQL DB and to include whatever PHP code they want inside brackets {}. This can be very useful for example for multi-language websites..etc..
I hope you understand my point.
Thanks

Answer 1

Do not use eval for this. Just do a simple search and replace.
From your question, tt's hard to understand where exactly the values for $name, $city and $age are stored. So, I'll just start from the point where you've retrieved that info. Let's say it's something like this:
$content = '<div> Hello my name is {$name}</div>
<span> I come from {$city}</span>
<div>I am {$age} years old</div>
';
$city = 'Kansas City';
echo str_replace('{$city}', $city, $content);
Also, in the sample code you've provided, the $content variable keeps getting over-written on each iteration of the while loop. Perhaps, that's what you want to happen or perhaps you wish to concatenate it.
Edit
After reading some of your comments, it seems that you will need a more dynamic solution. You can do so with something along the lines of:
if (preg_match_all('/{\$\w+}/', $content, $matches)) {
foreach ($matches[0] as $var) {
// var now contains the {$variableName}.
}
}
This will find the variables within your HTML, which you can then loop over, comparing against your file that contains the actual name/value pairs. Then use str_replace as shown above.

Answer 2

Why not just do this?
<div> Hello my name is <?=$name?></div>
<span> I come from <?=$name?></span>
<div>I am <?=$age?> years old</div>
For this to work, of course, you need the short_open_tag directive enabled. You can accomplish the same thing in more code without this enabled too:
<div> Hello my name is <?php echo $name ?></div>
<span> I come from <?php echo $name ?></span>
<div>I am <?php echo $age ?> years old</div>
You should really watch out for malicious users gaining access to this script though, because the way you envisioned it, they would be able to execute any code they so desired. Be sure to sanitize input and output of this script!