我应该如何计算PHP中字符串开头的字符出现次数

Question

The best that I have been able to come up with is:

strlen(preg_replace('/^([\\*]*)\s(.+)/',"$1",$line));
^^That seems to give the length of the string.^^

edit: I think that I should clarify that the character that I am trying to find is '*'

Answer 1

preg_match allows an output parameter which is filled with the matches, thus you can simply take the strlen of the match for the pattern /^**/:

$matches = array();
preg_match("/^\**/", $string, $matches);
$result =  strlen($matches[0]) ;

...

"***Hello world!*" -> 3
"Hello world!" -> 0