Is there any way i can write a struct's default constructor in C++/CLI

Question

// C3417.cpp
// compile with: /clr /c
value class VC {
   VC(){}   // C3417
   // OK
   static VC(){}
   VC(int i){}
};

Here is the sample MS show us about error C3417.But in a spcial case, I have to write the struct's default constructor like VC(){}.

Meanwhile i also find it really occurs in some API/SDK.Because i find the declare by using VS object explorer:

So,how can I write the code so that my C++/CLI assembly can export the default constructor of a struct?

Answer 1

Hi @Mage Luzdia,

A CLR type—for example, a class or struct—can have a static constructor that can be used to initialize static data members. A static constructor is called at most once, and is called before any static member of the type is accessed the first time.

using namespace System;

ref class MyClass {
private:
    static int i = 0;

    static MyClass() {
        Console::WriteLine("in static constructor");
        i = 9;
    }

public:
    static void Test() {
        i++;
        Console::WriteLine(i);
    }
};

int main() {
    MyClass::Test();
    MyClass::Test();
}

Best regards,

Elya

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