将枚举的所有选项填充为Nullable <Enum> 排列

Question

I have an Enum that needs to go into an Array that is Nullable :

StatusType?[] statusTypes = null; //Array to fill

I tried to fill the statusTypes like this:

statusTypes = (StatusType?[])Enum.GetValues(typeof(StatusType))

I receive the following error:

System.InvalidCastException: 'Unable to cast object of type 'x.Entities.Enums.StatusType[]' to type 'System.Nullable`1[x.Entities.Enums.StatusType][]'.'

How can I fill the Enum?[] with Enum[] ? I'm sure it is any easy fix, but I have been stumpted on it for a bit now. Thank you.

Answer 1

使用LINQ的Cast<T>()扩展方法并提供目标类型：

statusTypes = Enum.GetValues(typeof(StatusType)).Cast<StatusType?>().ToArray();

Answer 2

You can't just cast the arrays. The types are not compatible. You can use Array.ConvertAll to do the convertion:

Array.ConvertAll((StatusType[])Enum.GetValues(typeof(StatusType)), x => (StatusType?)x);