Get content between two strings PHP
-
22-07-2019 - |
Question
Whats is the best way to obtain the content between two strings e.g.
ob_start();
include('externalfile.html'); ## see below
$out = ob_get_contents();
ob_end_clean();
preg_match('/{FINDME}(.|\n*)+{\/FINDME}/',$out,$matches);
$match = $matches[0];
echo $match;
## I have used .|\n* as it needs to check for new lines. Is this correct?
## externalfile.html
{FINDME}
Text Here
{/FINDME}
For some reason this appears to work on one place in my code and not another. Am I going about this in the right way? Or is there a better way?
Also is output buffer the way to do this or file_get_contents?
Thanks in advance!
Solution
- Use
#
instead of/
so you dont have to escape them. - The modifier
s
makes.
and\s
also include newlines. {
and}
has various functionality like from n to m times in{n,m}
.The basic
preg_match('#\\{FINDME\\}(.+)\\{/FINDME\\}#s',$out,$matches);
The advanced for various tags etc (styling is not so nice by the javascript).
$delimiter = '#'; $startTag = '{FINDME}'; $endTag = '{/FINDME}'; $regex = $delimiter . preg_quote($startTag, $delimiter) . '(.*?)' . preg_quote($endTag, $delimiter) . $delimiter . 's'; preg_match($regex,$out,$matches);
Put this code in a function
- For any file which you do not want to execue any stray php code, you should use file_get_contents. include/require should not even be an option there.
OTHER TIPS
You may as well use substr and strpos for this.
$startsAt = strpos($out, "{FINDME}") + strlen("{FINDME}");
$endsAt = strpos($out, "{/FINDME}", $startsAt);
$result = substr($out, $startsAt, $endsAt - $startsAt);
You'll need to add error checking to handle the case where it doesn't FINDME.
I love these two solutions
function GetBetween($content,$start,$end)
{
$r = explode($start, $content);
if (isset($r[1])){
$r = explode($end, $r[1]);
return $r[0];
}
return '';
}
function get_string_between($string, $start, $end){
$string = " ".$string;
$ini = strpos($string,$start);
if ($ini == 0) return "";
$ini += strlen($start);
$len = strpos($string,$end,$ini) - $ini;
return substr($string,$ini,$len);
}
I also made few benchmarks as well with both solutions above and both are giving almost the same time. You can test it as well. I gave both functions a file to read which had about 60000 characters (reviewed with Ms. Word's word count) and both functions resulted in about 0.000999 seconds to find.
$startTime = microtime(true);
GetBetween($str, '<start>', '<end>');
echo "Explodin Function took: ".(microtime(true) - $startTime) . " to finish<br />";
$startTime = microtime(true);
get_string_between($str, '<start>', '<end>');
echo "Subsring Function took: ".(microtime(true) - $startTime) . " to finish<br />";
Line breaks can cause problems in RegEx, try removing or replacing them with \n before processing.
I like to avoid using regex if possible, here is alternative solution to fetch all strings between two strings and returns an array.
function getBetween($content, $start, $end) {
$n = explode($start, $content);
$result = Array();
foreach ($n as $val) {
$pos = strpos($val, $end);
if ($pos !== false) {
$result[] = substr($val, 0, $pos);
}
}
return $result;
}
print_r(getBetween("The quick brown {{fox}} jumps over the lazy {{dog}}", "{{", "}}"));
Results :
Array
(
[0] => fox
[1] => dog
)
function getInbetweenStrings($start, $end, $str){
$matches = array();
$regex = "/$start([a-zA-Z0-9_]*)$end/";
preg_match_all($regex, $str, $matches);
return $matches[1];
}
$str = "C://@@ad_custom_attr1@@/@@upn@@/@@samaccountname@@";
$str_arr = getInbetweenStrings('@@', '@@', $str);
print_r($str_arr);
This is a PHP solution that returns the strings found between tags in a haystack. It works, but I haven't tested for efficiency. I needed this and was inspired by Adam Wright's answer on this page.
Returns an array() containing all the strings found between $tag and $end_symbold.$tag in $haystack, or FALSE if no $end_symbol.$tag was found hence no tag pair exists in the $haystack.
function str_between_tags($haystack, $tag, $end_symbol){
$c_end_tags = substr_count($haystack, $end_symbol.$tag);
if(!$c_end_tags) return FALSE;
for($i=0; $i<$c_end_tags; $i++){
$p_s = strpos($haystack, $tag, (($p_e)?$p_e+strlen($end_symbol.$tag):NULL) ) + strlen($tag );
$p_e = strpos($haystack, $end_symbol.$tag, $p_s);
$result[] = substr($haystack, $p_s, $p_e - $p_s);
}
return $result;
}
Quick way to put everything into one string.
$newlines = array("\t","\n","\r","\x20\x20","\0","\x0B");
$one_string = str_replace($newlines, "", html_entity_decode($content));