字母表作为字符串......怎么样？

Question

I've been looking and searching for a long time now, but I can't find any way in PHP to grab a string such as "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ" by telling it the input language or locale (not sure which is relevant... maybe both). In fact, I can't even find a non-PHP list of these online anywhere. Except for the USA.

Do I have to figure this out myself and then produce my own strings, or is this built into the language somehow and ready for me to "grab"?

Answer 1

If you know the first and last letter of your alphabet, it is possible to use a combination of mb_strtolower and a mb_range function I found here : GitHub rodneyrehm

$low_letters = mb_range('α', 'ω');
$upper_letters = array_map('mb_strtoupper', $low_letters);

echo implode('', array_merge($low_letters, $upper_letters)); // αβγδεζηθικλμνξοπρςστυφχψωΑΒΓΔΕΖΗΘΙΚΛΜΝΞΟΠΡΣΣΤΥΦΧΨΩ

And the code of the mb_range function (in case the GitHub disappear) :

 mb_internal_encoding('UTF-8');
/**
 * multibyte string compatible range('A', 'Z')
 *
 * @param string $start Character to start from (included)
 * @param string $end Character to end with (included)
 * @return array list of characters in unicode alphabet from $start to $end
 * @author Rodney Rehm
 */
function mb_range($start, $end) {
    // if start and end are the same, well, there's nothing to do
    if ($start == $end) {
        return array($start);
    }

    $_result = array();
    // get unicodes of start and end
    list(, $_start, $_end) = unpack("N*", mb_convert_encoding($start . $end, "UTF-32BE", "UTF-8"));
    // determine movement direction
    $_offset = $_start < $_end ? 1 : -1;
    $_current = $_start;
    while ($_current != $_end) {
        $_result[] = mb_convert_encoding(pack("N*", $_current), "UTF-8", "UTF-32BE");
        $_current += $_offset;
    }
    $_result[] = $end;
    return $_result;
}