use*_*342 0 c# polymorphism inheritance
我有一条错误消息告诉我:
'BankAccount.account'不包含'withdraw'的定义.
这是我的代码:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace BankAccounts
{
class account
{
protected string name;
protected float balance;
public account(string n, float b)
{
name = n;
balance = b;
}
public void deposit(float amt)
{
balance -= amt;
}
public void display()
{
Console.WriteLine("Name: {0}. Balance: {1}.", name, balance);
}
}
class savingaccount : account
{
static int accno = 1000;
int trans;
public savingaccount(string s, float b) : base(s, b)
{
trans = 0;
accno++;
}
public void withdraw (float amt)
{
if (trans >= 10)
{
Console.WriteLine("Number of transactions exceed 10.");
return;
}
if (balance - amt < 500)
Console.WriteLine("Below minimum balance.");
else
{
base.withdraw(amt);
trans++;
}
}
public void deposit(float amt)
{
if (trans >= 10)
{
Console.WriteLine("Number of transactions exceed 10.");
return;
}
base.deposit(amt);
trans++;
}
public void display()
{
Console.WriteLine("Name: {0}. Account no.: {1}. Balance: {2}", name, accno, balance);
}
}
class currentaccount : account
{
static int accno = 1000;
public currentaccount(string s, float b) : base(s, b)
{
accno++;
}
public void withdraw(float amt)
{
if (balance - amt < 0)
Console.WriteLine("No balance in account.");
else
balance -= amt;
}
public void display()
{
Console.WriteLine("Name: {0}. Account no.: {1}. Balance: {2}.", name, accno, balance);
}
}
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}
我不明白为什么它不承认它.它是类savingaccount中的一个方法.
你在打电话
base.withdraw(amt);
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来自你的班级savingsaccount.但是基类(account)没有这样的方法.所以编译器绝对正确.