preg_grep function does not find anything (php)

Question

I hate to ask that kind of question because the answer is either 'I am stupid' or 'there is strange problem with my computer'... (and the first one is probably the right one) But I am stuck on that :

$matches = preg_grep("(.+)","ThisIsATest");
error_log(count($matches), 3, "php.log");

The log gives me 0 , no matter what I give as a pattern... I can't understand why this $matches variable is always empty !

Answer 1

preg_grep不是用于搜索字符串，而是用于搜索字符串数组...您可能应该改用preg_match 。

Answer 2

This is the error you should be getting:

preg_grep() expects parameter 2 to be array, string given

This is a way to return one match (and you will only have 1 in this case) with preg_match :

preg_match("(.+)","ThisIsATest", $matches);
print_r($matches);

See IDEONE demo

To access the value using $matches[0] , you need to use preg_match_all :

preg_match_all("(.+)","ThisIsATest", $matches);
print_r($matches[0]);

See another demo

Answer 3

It seems that you are just using the wrong method:

if (preg_match('/(.+)/', "ThisIsATest")) {
   # Successful match
} else {
   # Match attempt failed
}