Domain.CheckingAccount.CheckingAccount C# (CSharp) Method

        public CheckingAccount(long accountNumber,
                               double initialAmount,
                               double creditLimit,
                               Customer accountOwner)
        {
            if (!AccountUtil.ValidAccountNumber(accountNumber))
            {
                throw new ArgumentException();
            }

            this.accountNumber = accountNumber;
            this.amount = initialAmount;
            this.creditLimit = creditLimit;
            this.accountOwner = accountOwner;
        }