Parsing Conditions? Eval?

[Adrian Schneider]

I have a standalone system where users enter HTML, and I want to have some conditions in it (such as hide left block if that option is enabled). Basically in the HTML they will have something like this:

<table align="center" cellpadding="0" cellspacing="0" width="760">
	<tr valign="top">
		{IFSHOWLEFTBLOCK}
		<td width="{LEFTBLOCKWIDTH}" class="leftblock">
{LEFTBLOCKS}
		</td>
		<td width="{LEFTBLOCKSPACERWIDTH}"><img src="{SPACERIMAGE}" width="{LEFTBLOCKSPACERWIDTH}" alt="" /></td>
		{/IFSHOWLEFTBLOCK}


		<td class="content">
{BLOGPOSTBIT}
		</td>


		{IFSHOWRIGHTBLOCK}
		<td width="{RIGHTBLOCKSPACERWIDTH}"><img src="{SPACERIMAGE}" alt="" width="{RIGHTBLOCKSPACERWIDTH}"/></td>
		<td width="{RIGHTBLOCKWIDTH}" class="rightblock">
{RIGHTBLOCKS}
		</td>
		{/IFSHOWRIGHTBLOCK}


	</tr>
</table>

Right now I am just using preg_replace to replace the {variables} with the corresponding $variable (preset ones, they can't use anything), and I want the same for conditions.

I'm thinking eval (but I've never used much of it before), so how would I go about doing this with the IFs? Right now I am using preg replace, so if the condition they enter is false, it replaces the condtiions with <!-- and --> (very cheap solution) and if true, replaces with "".

I do not want this like vBulletins, where it runs any PHP they enter in the conditions, only presets.

[Adrian Schneider]

/me bumps this thread

[Zero Tolerance]

Let's say you had:

PHP Code:

eval('$userpage = "' . fetch_template('YOUR_TEMPLATE') . '";'); 


Above that you would have:

PHP Code:

$vbulletin->templatecache['YOUR_TEMPLATE'] = str_replace(
                        array('{LEFTBLOCKSPACERWIDTH}'),
                        array($leftblockwidth),
                        $vbulletin->templatecache['YOUR_TEMPLATE']
                        ); 


Not sure about your if macro's though, best to just use an if in php:

PHP Code:

$leftblock = '';
if ($show['leftblock'])
{
    $leftblock = "whatever...";
} 


Hope that helps, be sure to change the array in the second code for the str_replace, and "YOUR_TEMPLATE"

- Zero Tolerance

[Adrian Schneider]

Hmm, I didn't know about the templatecache thing.. neat

Anyway I may have misunderstood, but I don't think that will help. The HTML that is being parsed is not powered by vBulletin (just stored in db).

$somevariable =

<table align="center" cellpadding="0" cellspacing="0" width="760">
	<tr valign="top">
		<?php
		if ($userinfo['showleftblock'])
		{
?>
		<td width="{LEFTBLOCKWIDTH}" class="leftblock">
<?php print $leftblockbit; ?>
		</td>
		<td width="{LEFTBLOCKSPACERWIDTH}"><img src="{SPACERIMAGE}" width="{LEFTBLOCKSPACERWIDTH}" alt="" /></td>
<?		}?>

Well I edited it quickly, say if I replaced it like so from the old {if} how would I have it run the PHP while keeping the variable intact? I've never used much of eval before, and I think that's what I need to do. I'm not sure if this makes much sense... :ermm:

[Zero Tolerance]

Ah, not vb, i see, well lets say your variable for the template was "$mytemplate", you'd replace all instances of "$vbulletin->templatecache['YOUR_TEMPLATE']" with "$mytemplate", and instead of:

PHP Code:

eval('$userpage = "' . fetch_template('YOUR_TEMPLATE') . '";'); 


You would have:

PHP Code:

eval('$mytemplate = "' .  $mytemplate. '";'); 


Again as for the if statement, it would be much better for you to do it in php itself instead of the template.

- Zero Tolerance

[Adrian Schneider]

What would the difference between standard $var = val; and the eval?

The users are the ones inputing the conditions, how would I do it as you are suggesting?