using System;

using System.Text.Json;

using System.Text.Json.Serialization;

using static PhoneNumbers.PhoneNumberUtil;

using PhoneNumbers;

​

public class Program

{

    public static void Main()

    {

        var phoneValidator = new PhoneValidator();

        var (isSuccess, _, countryCode) = phoneValidator.Validate("+85244106298"); //電話如果不合法，countryCode 就為空

        Console.WriteLine(isSuccess);

        Console.WriteLine(countryCode);

    }

}

​

public class PhoneValidator

{

    private readonly PhoneNumberUtil _phoneNumberUtil = PhoneNumberUtil.GetInstance();

​

    /// <summary>

    ///     驗證電話號碼

    /// </summary>

    /// <param name="interPhoneNumber">+8860911123456</param>

    /// <returns>(true, +886911123456)</returns>

    public (bool isSuccess, string interPhoneNumber, string countryCode) Validate(string interPhoneNumber)

    {

        try

        {

            var parsedPhoneNumber = this._phoneNumberUtil.Parse(interPhoneNumber, null);

​

            if (!this._phoneNumberUtil.IsValidNumber(parsedPhoneNumber))

            {

                return (false, default, default);

            }

​

            return (true, this._phoneNumberUtil.Format(parsedPhoneNumber, PhoneNumberFormat.E164),

                _phoneNumberUtil.GetRegionCodeForNumber(parsedPhoneNumber));

        }

        catch

        {

            return (false, default, default);

        }

    }

​

    /// <summary>

    ///     驗證電話號碼

    /// </summary>

    /// <param name="countryCallingCode">+886</param>

    /// <param name="phoneNumber">0911123456</param>

    /// <returns>(true, +886911123456)</returns>

    public (bool isSuccess, string interPhoneNumber, string countryCode) Validate(

        string countryCallingCode, string phoneNumber)

    {

        return this.Validate($"{countryCallingCode}{phoneNumber}");

    }

}