BB Code

Jmz · 10-24-2007, 10:19 PM

Hi,

Whats the best way of adding bb code to a variable?

I've been playing about with a function using str_replace but I have also read that using preg_replace is more efficient and safer, is this true?

Is there a better way I haven't heard of?

Wildhoney · 10-24-2007, 10:38 PM

I doubt it being more efficient for a simple BB parser. Safer, definitely, because with regex you can say if it doesn't have a closing tag then ignore it. That way you can ensure every single tag is closed and thus not affecting the rest of your website.

As for the answer, well, I'll let someone else answer that :) ! As I know they are typing as I type this.

bluesaga · 10-24-2007, 10:45 PM

I think this is what you mean:

PHP Code:


			

function BBParser($szInput)
{

 $aBBPattern = array(
                     '[b](.*?)[/b]' => '<b>\\1</b>',
                     '[i](.*?)[/i]' => '<i>\\1</i>'
                     );

 foreach( $aBBPattern as $szKey => $szValue )
 {
    $szPattern = '/'. preg_quote( $szKey, '/' ) .'/is';
    $szInput    = preg_replace( $szPattern, $szValue, $szInput );
 }

 return $szInput;

}

Jmz · 10-25-2007, 08:07 AM

Thanks for that :)

If I used the method above, how would I do things like:

Code:

[ u r l=http://www.google.com]Google[/ u r l ]

(without the spaces)

bluesaga · 10-25-2007, 08:30 AM

You do need to be able to understand preg pattern matching to be able to understand this, but something like:

PHP Code:


			

function BBParser($szInput)
{

 $aBBPattern = array(
                     '[b](.*?)[/b]' => '<b>\\1</b>',
                     '[i](.*?)[/i]' => '<i>\\1</i>',
                     '[url=([^\]+?)](.*?)[/url]' => '<a href="\\1">\\2</a>'
                     );

 foreach( $aBBPattern as $szKey => $szValue )
 {
    $szPattern = '/'. preg_quote( $szKey, '/' ) .'/is';
    $szInput    = preg_replace( $szPattern, $szValue, $szInput );
 }

 return $szInput;

}

Remember this isnt tested, but the theory is there :)

Jmz · 10-25-2007, 09:16 AM

Thanks :)

I'll test it out now.

Jmz · 10-25-2007, 09:40 AM

Nope, I'm lost lol :(

What I have at the minute is:

PHP Code:


			
function BBCode($text){
$BBCode = array("&" => "&amp;",
"<" => "&lt;",
">" => "&gt;",
"[b]" => "<b>",
"[/b]" => "</b>",
"[i]" => "<i>",
"[/i]" => "</i>",
"[u]" => "<u>",
"[/u]" => "</u>",
"[img]" => "<img src='",
"[/img]" => "'>");
$parsedtext = str_replace(array_keys($BBCode), array_values($BBCode), $text);
return $parsedtext;
}

That works fine but I want to change it to do it your way.

I've tried:

PHP Code:


			
function BBcode($szInput)
{

 $aBBPattern = array(
                     '[b](.*?)[/b]' => '<b>\\1</b>',
                     '[i](.*?)[/i]' => '<i>\\1</i>',
                     '[url=([^\]+?)](.*?)[/url]' => '<a href="\\1">\\2</a>'
                     );

 foreach( $aBBPattern as $szKey => $szValue )
 {
    $szPattern = '/'. preg_quote( $szKey, '/' ) .'/is';
    $szInput    = preg_replace( $szPattern, $szValue, $szInput );
 }

 return $szInput;

}

Although I get no errors with the above code the bb tags aren't replaced, where am I going wrong?

Gurnk · 10-25-2007, 10:42 AM

How are you setting up the string you want to parse?

It should look like this I think

PHP Code:


			
 $sting = "[ b ]My BBC[/ b]";
echo BBcode($string);

Wildhoney · 10-25-2007, 11:26 AM

I've redone your regex and removed the preg_quote.

PHP Code:


			
function BBcode($szInput)
{
 $aBBPattern = array(
                     '\[b\](.*?)\[\/b\]' => '<b>\\1</b>',
                     '\[i\](.*?)\[\/i\]' => '<i>\\1</i>',
                     '\[url="([http:\/\/]+[^"]+)"\](.*)\[\/url\]' => '<a href="\\1">\\2</a>'
                     );

 foreach( $aBBPattern as $szKey => $szValue )
 {
    $szPattern = '/'. $szKey .'/isU';
    $szInput    = preg_replace( $szPattern, $szValue, $szInput );
 }

 return $szInput;

}

Salathe · 10-25-2007, 11:35 AM

The problem with bluesaga's function is that the patterns are fed into preg_quote which renders them useless for your needs.

An amended function could be something along the lines of:

PHP Code:


			
function BBcode($szInput)
{    
    $aBBPattern = array(
        '<strong>\\1</strong>'  => '#\[b\](.*?)\[/b\]#is',
        '<em>\\1</em>'          => '#\[i\](.*?)\[/i\]#is',
        '<u>\\1</u>'            => '#\[u\](.*?)\[/u\]#is',
        '<img src="\\1" />'     => '#\[img\](.*?)\[/img\]#i',
        '<a href="\\1">\\1</a>' => '#\[url\](.*?)\[/url\]#i',
        '<a href="\\1">\\2</a>' => '#\[url=([^\]]+?)\](.*?)\[/url\]#i'
    );
    return preg_replace(array_values($aBBPattern), array_keys($aBBPattern), $szInput);
}

Jmz · 10-25-2007, 11:41 AM

Thats great, thanks a lot.

bluesaga · 10-25-2007, 11:51 AM

Lol, yea sorry i forgot to escape the patterns properly, got confused with the preg_quote....