RegEx - adding <ol> to a list

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December 22nd, 2011, 04:13 AM

Penzais

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Other - RegEx - adding <ol> to a list

I have a number of HTML lists that need a <ol> and </ol> at the beginning and end. The problem is the list length, (the number of <li>__LINK__</li> ) differs from cell to cell - I am using Excel to hold the formatted data for each record.

I am thinking I need to find the first <li> and replace with <ol><li> and the last </li> and replace with </li></ol>

My regex skill aren't up to scratch so any help is greatly appreciated.

December 22nd, 2011, 08:23 AM

ManiacDan

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Show some example data. Is there really ONE first <li> and ONE last </li>? If so, that's very easy.

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December 22nd, 2011, 02:12 PM

ragax

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Hi Penzais,

As ManiacDan was saying, seeing sample data always helps write the expression.

In the meantime, if I understood your requirements, this code might work.

A. Replacing the first <li>

PHP Code:


		
			
 $result = preg_replace('/(?is)<li>/', '<ol><li>', $string,1);

It's a simple preg_replace on a multiple-line string, case insensitive.
The key here is the last argument: the 1 says "make one replacement then stop".

B. Replacing the last </li>

PHP Code:


		
			
 $result = preg_replace('%(?is).*</li>%', '</li></ol>', $string);

Here we don't need the "1". Because of the greedy star, the regex engine shoots all the way to the end of the string, then backtracks to match the very last </li>

The i and s modes are turned on inline but you could turn them on after the pattern string if you prefer.

I haven't tested those but am hopeful that I didn't introduce a bug of some kind. Give it a whirl and let me know how you go, happy to help you tweak it if it doesn't do the job.

Other - RegEx - adding <ol> to a list

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