formatDigitPattern static method
每隔 x 位加 pattern。比如用来格式化银行卡
Implementation
static String formatDigitPattern(String text, {int digit = 4, String pattern = ' '}) {
final regex = RegExp('(.{$digit})');
return text.replaceAllMapped(regex, (match) => '${match.group(0)}$pattern').replaceAll(RegExp('$pattern\$'), '');
}