How do I use preg_match in PHP to get the substring D30 in the following string?
$string = "random text sample=D30 more random text";
1 Answer
preg_match() will assign the match groups to the third parameter and return the 1 on match and 0 on no match. So check if preg_match() == true, and if it is, your value will be in $matches[0].
$string = "random text sample=D30 more random text";
if(preg_match('/(?<=sample=)\S+/', $string, $matches)) {
$value = reset($matches);
echo $value; // D30
}
RegEx:
(?<= (?# start lookbehind)
sample= (?# match sample= literally)
) (?# end lookbehind)
\S+ (?# match 1+ characters of non-whitespace)
Using capture groups instead of lookbehind:
$string = "random text sample=D30 more random text";
if(preg_match('/sample=(\S+)/', $string, $matches)) {
$value = $matches[1];
echo $value; // D30
}
RegEx:
sample= (?# match sample= literally)
( (?# start capture group)
\S+ (?# match 1+ characters of non-whitespace)
) (?# end capture group)
3 Comments
user3388884
This demo returned "No match groups were extracted"... wh
Sam
I didn't use any match groups, instead I only matched the part you wanted..meaning your value is in
$matches[0] not $matches[1]. I'll update with an alternative method.Sam
Accept if it helped, I also included an example using capture groups instead of lookarounds. I prefer the lookaround method when possible, but its good to be familiar with both.
preg_match()for this. Just useexplode():$result = explode('=', $str)[1];.