如何比较arabic-和假名全宽数字？

Question

How can I compare in PHP the two strings

県１９−１県２２５−３県９６−１

and

県19-1県225-3県96-1

?

The first one contains kana full-width numbers, the comparison should treat them as equal to the arabic-numeral.

Answer 1

You can convert all the zen-kaku (fullwidth) characters to their han-kaku (halfwidth) equivalents first using the mb_convert_kana() function, and then do the comparison, like this:

$string1 = "県１９−１県２２５−３県９６−１";
$string2 = "県19-1県225-3県96-1";
var_dump($string1 === $string2);    // This is false because they are different.

// Convert fullwidth to halfwidth.
$string1 = mb_convert_kana($string1, "a");    // Specify "a" for converting both alphabets
$string2 = mb_convert_kana($string2, "a");    // and numbers. See doc for other options.
var_dump($string1 === $string2);    // This becomes true, both are "県19-1県225-3県96-1".

Note that mb_convert_kana() is in the mbstring extension which is not a default extension, so you may have to install it first.