如何计算比赛次数？ [重复]

I have a string like this:

$str = 'this is a string';

And this is my pattern: /i/g. There is three occurrence (as you see in the string above, it is containing three i). Now I need to count that. How can I get that number?

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you can use substr_count() as well as preg_match_all()

echo substr_count("this is a string", "i"); // will echo 3
echo $k_count = preg_match_all('/i/i', 'this is a string', $out);  // will echo 3

other method is convert into array and then count it:

$arr = str_split('this is a string');
$counts = array_count_values($arr);

print_r($counts);

output:

Array
(
    [t] => 2
    [h] => 1
    [i] => 3
    [s] => 3
    [ ] => 3
    [a] => 1
    [r] => 1
    [n] => 1
    [g] => 1
)

You should use substr_count().

$str = 'this is a string';
echo substr_count($str, "i"); // 3

You can also use mb_substr_count()

$str = 'this is a string';
echo mb_substr_count($str, "i"); // 3

substr_count — Count the number of substring occurrences

mb_substr_count — Count the number of substring occurrences

preg_match_all could be a better fit.

Here is an example:

<?php
$subject = "a test string a";
$pattern = '/a/i';
preg_match_all($pattern, $subject, $matches);
print_r($matches);
?>

Prints:

Array ( [0] => Array ( [0] => a [1] => a ) )