如何在C＃中调用使用指针作为参数的DLL函数C ++？

如何解决如何在C＃中调用使用指针作为参数的DLL函数C ++？

我正在尝试在C＃中调用一个称为Function_A（Class1 * input_class）的DLL函数（用C ++编写）。这是我在C＃中声明的类。我已经读过有关在Function_A声明中某处使用ref关键字的信息，但不确定。任何帮助将不胜感激。谢谢！

[DllImport("The_DLL.dll")]
public static extern int Function_A(Class1* input_class);

public struct Class1
{
        int vara;
        int varB;
}

public struct Class2
{
        class1 class1_A;
        class1 class1_B;
}

static void Main(string[] args)
{
        Class2 a = new Class2();
        Function_A(...);
}

解决方法

[DllImport("The_DLL.dll")]
public static extern int Function_A([In,Out]Class1 input_class);

[DllImport("The_DLL.dll",EntryPoint="Function_A")]
public static extern int Function_A2(ref Class1 input_class);


[StructLayout(LayoutKind.Sequential)]
public struct Class1 //a bad name for a struct but hey...
{
        int varA;
        int varB;
}


static void Main(string[] args)
{
        Class1 x = new Class1();
        Function_A(x); // your struct is marshalled so that changes by the external function are marshalled back
        Function_A2(x); // your struct is marshalled so that changes by the external function are NOT marshalled back
}