getMatchingPrefix method
Get the matching prefix for a phone number
Implementation
String? getMatchingPrefix(String phoneNumber) {
if (phoneNumber.isEmpty) return null;
final cleanNumber = phoneNumber.replaceAll(RegExp(r'[\s\-]'), '');
for (final prefix in validPrefixes) {
if (cleanNumber.startsWith(prefix)) {
return prefix;
}
}
return null;
}