php - 如何在使用php提到的以下段落中找到字母't'的计数

Question

$a='Would you like to have responses to your questions sent to you via email'

for($a as $b=>c){

}

请给我解决方案

Answer 1

<?php echo substr_count($a, 't'); ?>

Answer 2

这是一个解决方案，虽然不一定是最好的

$letterCount = array_count_values(
    str_split(strtolower($a))
);
$tCount = (isset($letterCount['t'])) ? $letterCount['t'] : 0;

Answer 3

$count = preg_match_all('/t/', $str);

Answer 4

检查这个

<?php

$a = 'Would you like to have responses to your questions sent to you via email';

$t_explod = explode('t', strtolower($a));

echo count($t_explod) - 1;
?>