將結構數組從 C++ 傳遞到 C#

Question

我正在使用無法轉換為 .NET 的大型遺留 C++ 6.0 代碼庫。 我想做的是在 C# 中編寫所有新功能，用 COM 包裝器包裝它，然后從 C++ 調用它。 我遇到了大量從 C# 調用 C++ 的文章，但反過來卻很少。 The interaction between C# and C++ is working fine for me for simple types, however I have hit a problem, I need to pass an array of type Variable(user defined) from C++ to C#, when I import the type library I get the following我在 c# 中聲明數組的任何方法的行

由於返回類型或參數類型無效，未發出方法“ParseEquation”

誰能告訴我如何將用戶定義的 class 數組從 C++ 傳遞到 C# 代碼這里是代碼。

c#代碼

//  Equation Parser


//Events Interface
[ComVisible(true), Guid("47C976E0-C208-4740-AC42-41212D3C34F0"), InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
public interface IEquation_EventsCOM
{
}

//COM Interface
[ComVisible(true), Guid("3F2DE348-0BDA-4051-92B5-9B7A59FD525D")]
public interface IEquationCOM
{
    [DispId(0)]
    string GetParserInfo();

    [DispId(1)]
    float ParseEquation(IVariableCOM[] varList, string expression);
}

[ComVisible(true), Guid("9E5E5FB2-219D-4ee7-AB27-E4DBED8E123E"), ClassInterface(ClassInterfaceType.None), ComSourceInterfaces(typeof(IEquation_EventsCOM))]
public class Equation : IEquationCOM
{
    public Equation()
    {
    }

    [ComVisible(true)]
    public string GetParserInfo()//List<Variable> varList, string expression)
    {
        Version version = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version;
        string name = System.Reflection.Assembly.GetExecutingAssembly().GetName().FullName;
        return "Assemby Name: " + name + "   Version: " + version.ToString();
    }

    [ComVisible(true)]
    public float ParseEquation(IVariableCOM[] varList, string expression)
    {
        //test return value
        return 12.0000f;
    }
}


//  Equation Parser Helper Classes

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct IVariableCOM
{
    public string Name;
    public string Type;
    public float Value;
}

header 通過導入類型庫在 C++ 中生成

// Machine generated IDispatch wrapper class(es) created with ClassWizard
/////////////////////////////////////////////////////////////////////////////
// IEquation_EventsCOM wrapper class

class IEquation_EventsCOM : public COleDispatchDriver
{
public:
    IEquation_EventsCOM() {}        // Calls COleDispatchDriver default     constructor
    IEquation_EventsCOM(LPDISPATCH pDispatch) : COleDispatchDriver(pDispatch) {}
    IEquation_EventsCOM(const IEquation_EventsCOM& dispatchSrc) :     COleDispatchDriver(dispatchSrc) {}

// Attributes
public:

// Operations
public:
};
/////////////////////////////////////////////////////////////////////////////
// IEquationCOM wrapper class

class IEquationCOM : public COleDispatchDriver
{
public:
    IEquationCOM() {}       // Calls COleDispatchDriver default constructor
    IEquationCOM(LPDISPATCH pDispatch) : COleDispatchDriver(pDispatch) {}
    IEquationCOM(const IEquationCOM& dispatchSrc) : COleDispatchDriver(dispatchSrc) {}

// Attributes
public:

// Operations
public:
    CString GetGetParserInfo();
    // method 'ParseEquation' not emitted because of invalid return type or parameter     type
};

Answer 1

您通過 IDispatch 接口導入要使用的庫。 這允許您僅公開原始（int、string、fload、arrays 等）和其他對象（也必須實現 IDispatch）。

因此，您應該用新的 IDispatch 接口 + 實現定義替換 Struct (struct IVariableCOM)（類似於您公開 IEquationCOM/Equation）。

A low level solution (you should known the COM rules: memory management, etc): If you are using the COM objects only from c++, you can extract the idl file, and compile it on your c++ project where you can access the IVariableCOM definition .