Count the number of substring occurrences (PHP 4 >= 4.3.0, PHP 5)
int mb_substr_count ( string haystack, string needle [, string encoding] )

mb_substr_count() returns the number of times the needle substring occurs in the haystack string.

encoding specifies the encoding for needle and haystack. If omitted, internal character encoding is used.

例 1201. mb_substr_count() example

echo mb_substr_count("This is a test", "is"); // prints out 2

See also substr_count(), mb_strpos(), mb_substr().