Explode a paragraph into sentences in PHP

Question

I have been using

explode(".",$mystring)

to split a paragraph into sentences. However this doen't cover sentences that have been concluded with different punctuation such as ! ? : ;

Is there a way of using an array as a delimiter instead of a single character? Alternativly is there another neat way of splitting using various punctuation?

I tried

explode(("." || "?" || "!"),$mystring)

hopefully but it didn't work...

Answer 1

You can do:

preg_split('/\.|\?|!/',$mystring);

or (simpler):

preg_split('/[.?!]/',$mystring);

Answer 2

You can use preg_split() combined with a PCRE lookahead condition to split the string after each occurance of ., ;, :, ?, !, .. while keeping the actual punctuation intact:

Code:

$subject = 'abc sdfs.    def ghi; this is an.email@addre.ss! asdasdasd? abc xyz';
// split on whitespace between sentences preceded by a punctuation mark
$result = preg_split('/(?<=[.?!;:])\s+/', $subject, -1, PREG_SPLIT_NO_EMPTY);
print_r($result);

Result:

Array
(
    [0] => abc sdfs.
    [1] => def ghi;
    [2] => this is an.email@addre.ss!
    [3] => asdasdasd?
    [4] => abc xyz
)

You can also add a blacklist for abbreviations (Mr., Mrs., Dr., ..) that should not be split into own sentences by inserting a negative lookbehind assertion:

$subject = 'abc sdfs.   Dr. Foo said he is not a sentence; asdasdasd? abc xyz';
// split on whitespace between sentences preceded by a punctuation mark
$result = preg_split('/(?<!Mr.|Mrs.|Dr.)(?<=[.?!;:])\s+/', $subject, -1, PREG_SPLIT_NO_EMPTY);
print_r($result);

Result:

Array
(
    [0] => abc sdfs.
    [1] => Dr. Foo said he is not a sentence;
    [2] => asdasdasd?
    [3] => abc xyz
)

Answer 3

Assuming that you actually want the punctuations marks with the end result, have you tried:

 $mystring = str_replace("?","?---",str_replace(".",".---",str_replace("!","!---",$mystring)));
 $tmp = explode("---",$mystring);

Which would leave your punctuation marks in tact.

Answer 4

preg_split('/\s+|[.?!]/',$string);

A possible problem might be if there is an email address as it could split it onto a new line half way through.

Answer 5

Use preg_split and give it a regex like [\.|\?!] to split on

Answer 6

You can't have multiple delimiters for explode. That's what preg_split(); is for. But even then, it explodes at the delimiter, so you will get sentences returned without the punctuation marks. You can take preg_split a step farther and flag it to return them in their own elements with PREG_SPLIT_DELIM_CAPTURE and then run some loop to implode sentence and following punctation mark in the returned array, or just use preg_match_all();:

preg_match_all('~.*?[?.!]~s', $string, $sentences);

Answer 7

$mylist = preg_split("/[.?!:;]/", $mystring);

Answer 8

You can try preg_split

$sentences = preg_split("/[.?!:;]+/", $mystring);

Please note this will remove the punctuations. If you would like to strip out leading or trailing whitespace as well

$sentences = preg_split("/[.?!:;]+\s+?/", $mystring);