C#:与名单,其中继承问题; T>名单、问题、GT

2023-09-02 21:12:13 作者:岁月静好怎敢老去

让我们假设这个类在C#:

Let's assume this class in C#:

public class LimitedList<T> : List<T>
{
    private int _maxitems = 500;

    public void Add(T value) /* Adding a new Value to the buffer */
    {
        base.Add(value);
        TrimData(); /* Delete old data if lenght too long */
    }

    private void TrimData()
    {
        int num = Math.Max(0, base.Count - _maxitems);
        base.RemoveRange(0, num);
    }
}

编译器给了我这个警告在该行公共无效添加(T值):

The compiler gives me this warning in the line "public void Add(T value)":

警告CS0108:System.LimitedList.Add(T)隐藏了继承的成员System.Collections.Generic.List.Add(T)。使用new关键字,如果隐藏之意。

warning CS0108: 'System.LimitedList.Add(T)' hides inherited member 'System.Collections.Generic.List.Add(T)'. Use the new keyword if hiding was intended.

什么我必须做的,以避免这样的警告?

What do I have to do to avoid this warning?

THX 4你的帮助

推荐答案

没有 - 不要使用在这里;这不给你多态。 名单,其中,T&GT; 不适合继承这种方式;使用收藏&LT; T&GT; 覆盖添加 InsertItem 方法。

No - don't use new here; that doesn't give you polymorphism. List<T> isn't intended for inheritance in this way; use Collection<T> and override the Add InsertItem method.

public class LimitedCollection<T> : Collection<T>
{
    private int _maxitems = 500;

    protected override void InsertItem(int index, T item)
    {
        base.InsertItem(index, item);
        TrimData(); /* Delete old data if lenght too long */
    }

    private void TrimData()
    {
        int num = Math.Max(0, base.Count - _maxitems);
        while (num > 0)
        {
            base.RemoveAt(0);
            num--;
        }
    }
}