如何检查列表是否包含某种类型的对象? C# [英] How do I check if a List contains an object of a certain type? C#
问题描述
我有一个列表(称为 Within
),其中包含类型为 GameObject
的对象。
GameObject
是许多其他人的父类,包括 Dog
和 Ball
。我想制作一个方法,如果内部包含任何类型为 Ball
的对象,则返回true,但是我不知道该怎么做。
I have a list (called Within
), and it contains objects of type GameObject
.
GameObject
is a parent class to many others, including Dog
and Ball
. I want to make a method that returns true if Within contains any object of type Ball
, but I don't know how to do this.
我尝试使用 Count<>
, Any<>
, Find<>
和C#中提供的其他一些方法,但我无法使它们正常工作。
I've tried using Count<>
, Any<>
, Find<>
and a few other methods provided within C#, but I couldn't get them to work.
public bool DetectBall(List<GameObject> Within)
{
//if Within contains any object of type ball:
{
return true;
}
}
推荐答案
if (within.OfType<Ball>().Any())
除 Cast< T>()
和 OfType< T>()
之外的所有LINQ方法的通用参数为用于允许方法调用进行编译,并且必须与列表的类型兼容(或对于协变强制转换)。它们不能用于按类型过滤。
The generic parameter of all LINQ methods except Cast<T>()
and OfType<T>()
is used to allow the method call to compile and must be compatible with the type of the list (or for a covariant cast). They cannot be used to filter by type.
这篇关于如何检查列表是否包含某种类型的对象? C#的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!