isIPAddress static method
验证IP地址
Implementation
static bool isIPAddress(String? ip) {
if (ip?.isEmpty ?? true) return false;
final parts = ip!.split('.');
if (parts.length != 4) return false;
return parts.every((part) {
final num = int.tryParse(part);
return num != null && num >= 0 && num <= 255;
});
}