>>780

オレなら

<html>
<form method="post" action="">
<textarea name="body"></textarea>
<input type="submit">
</form>
</html>
<?php
$value = trim( $_POST['body'] );
echo '[' . $value . ']';

$mb_length = mb_strlen($value);

$length = strlen($value);

echo "全角";
echo ($length - $mb_length) / 2;

echo "半角";
echo $mb_length - ($length - $mb_length) / 2;