Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Cell/Coordinate.php
public static function coordinateFromString($pCoordinateString)
    {
        if (preg_match('/^([$]?[A-Z]{1,3})([$]?\\d{1,7})$/', $pCoordinateString, $matches)) {
            return [$matches[1], $matches[2]];
        } elseif (self::coordinateIsRange($pCoordinateString)) {
            throw new Exception('Cell coordinate string can not be a range of cells');
        } elseif ($pCoordinateString == '') {
            throw new Exception('Cell coordinate can not be zero-length string');
        }

        throw new Exception('Invalid cell coordinate ' . $pCoordinateString);
    }
public static function coordinateFromString($pCoordinateString)
    {
        if (preg_match('/^([$]?[A-Z]{1,3})([$]?\\d{1,7})$/', $pCoordinateString, $matches)) {
            return [$matches[1], $matches[2]];
        } elseif (self::coordinateIsRange($pCoordinateString)) {
            throw new Exception('Cell coordinate string can not be a range of cells');
        } elseif ($pCoordinateString == '') {
            throw new Exception('Cell coordinate can not be zero-length string');
        }

        throw new Exception('Invalid cell coordinate ' . $pCoordinateString);
    }
Coordinate from string.

@param string $pCoordinateString eg: 'A1'

@throws Exception

@return string[] Array containing column and row (indexes 0 and 1)