What is the C++ CLI equivalent of managed c++'s __typeof and __gc?

Question

I'm trying to convert an old c++ project from VS2003 to VS2019. Part of this, I'm learning, is going from managed C++ to C++ CLI as managed c++ was dropped pretty quickly.

I'm managing for the most part, but I can't seem to figure out what replaces the __typeof keyword. Is there a drop in for this? See below code snippet for context in how it was it's used.

private: System::ComponentModel::IContainer ^  components;

    private:
        void InitializeComponent(void)
        {
            this->components = gcnew System::ComponentModel::Container();
            System::Resources::ResourceManager ^  resources = gcnew System::Resources::ResourceManager(__typeof(USB::Form1));
            .
            .
            .
        }

Additionally, there's another reoccurring identifier, __gc , that I have found some more info on, but am not sure I understand what to replace it with.

Char chars __gc[] = gcnew Char __gc[bytes->Length * 2];
Char hexDigits __gc[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
bool ImageNumberUsed __gc[];

Does anyone have a good grasp on this and know what the proper conversions are given above contexts?

Answer 1

I can't say that I've used much Managed C++, but I can say what the C++/CLI equivalents are.

• __typeof(type) --> type::typeid
  • Access typeid as if it were a static field or property of the given type.
  • Returns an object of type System::Type^.
  • Example: gcnew System::Resources::ResourceManager(USB::Form1::typeid);
• __gc[] --> class cli::array
  • cli::array is a full-fledged managed type. You create it with gcnew, variables are declared with the hat ^, etc.
  • cli::array is generic on the type of object stored in the array, and on the number of dimensions in the array (which defaults to 1). The size of the array is specified via a constructor parameter (using parentheses, not square brackets).
  • Variables are declared with the name of the type, cli::array. Square brackets are used for reading & writing values, not for declaring the type, nor for creating the array.
  • If the type inside the array is a managed reference type, you'll need to include the hat ^ inside the generic type. Example: cli::array<String^>^ foo = ...
  • Examples:
    • cli::array<System::Char>^ chars = gcnew cli::array<System::Char>(bytes->Length * 2);
    • cli::array<System::Char>^ hexDigits = { '0', '1', .... };
      • (I like to say System.Char, as an extra reminder that it's not the same thing as lower-case char.)
    • cli::array<bool>^ ImageNumberUsed; (Uninitialized or null until assigned)
    • Two-dimensional: cli::Array<String^, 2>^ stringGrid = gcnew cli::Array<String^, 2>(10, 10);