lookupCountryIdentifier method
Implementation
String? lookupCountryIdentifier(String productCode) {
initIfNeeded();
final prefix = int.parse(productCode.substring(0, 3));
final max = ranges.length;
for (int i = 0; i < max; i++) {
final range = ranges[i];
final start = range[0];
if (prefix < start) {
return null;
}
final end = range.length == 1 ? start : range[1];
if (prefix <= end) {
return countryIdentifiers[i];
}
}
return null;
}