问从PHPExcel中的列名创建列索引

EN

$column = 'IV';
$columnIndex = PHPExcel_Cell::columnIndexFromString($column);

public static function lettersToInt(string $string): int {
    $letters = str_split($string);
    $lastLetter = array_pop($letters); // Last letter is defining number between 0-26
    $index = 0;
    $alphabet = range('A', 'Z');
    foreach($letters as $letter) {
        // Letters before last letter are defining how many times to add 26.
        $multiplier = array_search($letter, $alphabet) + 1;
        $index = $index + 26 * $multiplier;
    }
    $index = $index + array_search($lastLetter, $alphabet);
    return $index;
}