public void Withdraw(double amount)
{
Console.WriteLine("{0}取款{1}", this.owner, amount);
state.Withdraw(amount); //调用状态对象的Withdraw()方法
Console.WriteLine("现在余额为{0}", this.Balance);
Console.WriteLine("现在帐户状态为{0}", this.state.GetType().ToString());
Console.WriteLine("---------------------------------------------");
}
