Extracting quotes with regular expressions

[kickstart]

Hi

 

Trying to work out how to do this, but I am very weak at regular expressions.

 

If I have a string as follows:-

 

The quick "brown fox" jumped over the "lazy dog"

 

I would like to extract the quotes strings (ie brown fox and lazy dog)

 

Think I can do this with the following:-

 

preg_match_all( '/".*?"/', 'The quick "brown fox" jumped over the "lazy dog"', $matches )

 

which will put each of the quoted strings into an array.

 

However I would also like a way to extract the rest of the string separately - preferably without looping round the extracted array.

 

Also, if I wanted to cope with strings enclosed in single quotes as well as double quotes, how can I expand it to cover that?

 

Thank you

 

All the best

 

Keith

 

 

[ignace]

This is possibly done better and faster without regex. Regex would require you to regex twice. Once for everything between " and once for everything that is not between ".

[Barand]

non-regex solution

 

<?php

$str = 'The quick "brown fox" jumps over the "lazy dog".';

$result = xQuotes($str);

echo '<pre>'.print_r($result, 1).'</pre>';

function xQuotes($str) 
{
    $k = strlen($str);
    $i = $j = 0;
    $res = array();
    $inquotes = false;
    for ($i=0; $i<$k; ++$i) {
        switch($c = $str[$i]) {
            case '"':
                if (!$inquotes) ++$j;
                $inquotes = !$inquotes;
                break;
            default:
                $index = $inquotes ? $j : 0;
                if (isset($res[$index])) 
                    $res[$index] .= $c;
                else
                    $res[$index] = $c;
                break;       
        }
    }
    return $res;
}
?>

 

results==>

Array

(

    0 => The quick  jumps over the .

    1 => brown fox

    2 => lazy dog

)

[kickstart]

Hi

 

Cheers. I thought a regex would have been the quickest, but it is a non trivial one it would seem.

 

I will have a play with Barands solution, but modify it to cope with single quote delimited strings as well as double quote delimited strings.

 

As an aside '/(".*?")|(\'.*?\')/' works to extract single and double quoted strings (just not found a way to extract things other than those).

 

Thank you

 

All the best

 

Keith

[kickstart]

Hi

 

Played with Barands script to cope with both single and double quoted strings.

 

function xQuotes($str) 
{
$str_array = str_split($str);
$j = 0;
    $res = array();
    $insinglequotes = false;
    $indoublequotes = false;
foreach($str_array AS $str_item)
{
        switch(true) 
	{
            case $str_item == "'" AND !$indoublequotes:
			if (!$insinglequotes) ++$j;
			$insinglequotes = !$insinglequotes;
			break;
            case $str_item == '"' AND !$insinglequotes:
			if (!$indoublequotes) ++$j;
			$indoublequotes = !$indoublequotes;
                break;
            default:
                $index = (($insinglequotes || $indoublequotes) ? $j : 0);
                if (isset($res[$index])) 
                    $res[$index] .= $str_item;
                else
                    $res[$index] = $str_item;
                break;       
        }
    }
if ($insinglequotes || $indoublequotes)
{
	$res[0] .= $res[$j];
	unset($res[$j]);
}
    return $res;
}

 

All the best

 

Keith

[ignace]

Is the double case really necessary?

 

case ($str_item === '"' || $str_item === "'") && !$indoublequotes:

[kickstart]

Hi

 

Afraid I think it is, to cope with entries delimited by either double quotes or single quotes, and to ignore any single quotes within double quotes.

 

All the best

 

Keith