linq - 类型转换和Linq Cast <T>()

Question

尝试回答this question时，我发现了以下内容:

string s = "test";

var result1 = s.Select(c => (ushort)c); // works fine

var result2 = s.Cast<ushort>(); // throws an invalid cast exception

为什么Cast<T>()在这里失败？有什么不同？

Answer 1

想您会在这里找到答案:

Puzzling Enumerable.Cast InvalidCastException

最后一部分，在“编辑”下:

Cast<T>() is an extension method on IEnumerable rather than IEnumerable<T>. That means that by the time each value gets to the point where it's being cast, it has already been boxed back into a System.Object