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How do I count results in a nested array generated by Preg_Match


marmelade7

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My goal is to reliably count the number of matches in a preg_match_all operation.
 

The following code works fine in a separate PHP page.  However, it does NOT work when I include it in other php code.  Same code: different result.

 

preg_match_all('/[0-9]{1,}[-]{1}[0-9]{1,}/',$txt,$matches);
$c=count($matches[0]);
preg_match_all('/[A-Za-z]{1,}[-]{1}[A-Za-z]{1,}/',$txt,$matches);
$d=count($matches[0]);

echo "c count=".$c;

echo "d count="$d; 

Why does this code NOT work when I include it in other PHP code, even though this code works in a php page by itself?

 

How can I reliably count the number of matches in a preg_match_all operation.  I know I use "matches" and I know there are nested arrays.  However the statement count($matches[0]) does not always work.

 

 

 

 

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1 hour ago, marmelade7 said:

But how DO I count the matches? I've already looked at examples but I still don't get it.

Did you check the link I gave? It pointed you to the Return Values section (or at least it was supposed to).

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I've already been through all that stuff.  I need someone to explain where the answer is.  I've deduced that count($matches[0]) contains the answer, but count($matches[0]) does not always work. The examples show me how to print the results in the array -- I still do not see how to count them.

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 I was hoping for a specific example that shows a preg_match_all statement that ends up with something like: $totalMatchedItems=5.  The examples I see show a bunch of array info, but don't make it clear (at least not to me) how to count these nested arrays.

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4 hours ago, marmelade7 said:

I've already been through all that stuff.  I need someone to explain where the answer is.  I've deduced that count($matches[0]) contains the answer, but count($matches[0]) does not always work.

It seems like you are fixed on using $matches.  People tried a few different ways to tell you that the function returns the number of matches, so this is your original code re-written.

$c = preg_match_all('/[0-9]{1,}[-]{1}[0-9]{1,}/', $txt, $matches);
$d = preg_match_all('/[A-Za-z]{1,}[-]{1}[A-Za-z]{1,}/', $txt, $matches);

echo "c count=$c";
echo "d count=$d";

 

The reason for this, is that any regex can have groupings (capture groups) that produce partial matches, and all of these are returned in the $matches array.  The return value only returns the actual number of full matches, which is clearly what you want.

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