c# - 在 CLR C++ 中用数组初始化 List？

Question

我想知道为什么这段代码在 C++/CLI 中不起作用，但在 C# 中却很容易？

List<Process^>^ processList = gcnew List<Process^>(
  Process::GetProcessesByName(this->processName)););

error C2664: 'System::Collections::Generic::List::List(System::Collections::Generic::IEnumerable ^)' : cannot convert parameter 1 from 'cli::array ^' to 'System::Collections::Generic::IEnumerable ^'

这是我想出的。做得很好。 :)

List<Process^>^ processList = gcnew List<Process^>(
  safe_cast<System::Collections::Generic::IEnumerable<Process^>^>
    (Process::GetProcessesByName(this->processName)));

Answer 1

您需要使用 safe_cast .根据MSDN documentation on System::Array ,

Important

Starting with the .NET Framework 2.0, the Array class implements the System.Collections.Generic::IList<T>, System.Collections.Generic::ICollection<T>, and System.Collections.Generic::IEnumerable<T> generic interfaces. The implementations are provided to arrays at run time, and therefore are not visible to the documentation build tools. As a result, the generic interfaces do not appear in the declaration syntax for the Array class, and there are no reference topics for interface members that are accessible only by casting an array to the generic interface type (explicit interface implementations). The key thing to be aware of when you cast an array to one of these interfaces is that members which add, insert, or remove elements throw NotSupportedException.

如您所见，强制转换必须在运行时在 C++ 中显式完成，例如

List<Process^>^ processList = gcnew List<Process^>(
    safe_cast<IEnumerable<T> ^>(
        Process::GetProcessesByName(this->processName)));