如何將包含void *的結構從c ++傳遞給c＃？

Question

我遇到問題，無法在網上找到答案。 我想從我的C＃代碼中調用C ++函數。 c ++函數聲明為：

int read(InfoStruct *pInfo, int size, BOOL flag)

具有以下結構

typedef struct
{
    int ID; 
    char Name[20];
    double value;
    void *Pointer;
    int time;
}InfoStruct;

在我的C＃代碼中，我寫道：

 public unsafe struct InfoStruct
 {
    public Int32 ID;
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 20)]
    public string Name;
    public Double value;
    public void *Pointer;
    public Int32 time;
  };

[DllImport("mydll.dll", SetLastError = true, CharSet = CharSet.Auto, CallingConvention = CallingConvention.Cdecl)]
        public static extern unsafe int read(out MeasurementInfoStruct[] pInfo, int size, bool flag);

我試圖運行代碼，但是它崩潰了，所以我想我特別是在void *結構上犯了一個錯誤，但我不知道該放什么。 函數返回一個結構數組的事實也可能是事實，也許我沒有正確地稱呼它。 你能幫我嗎？ 非常感謝。

Answer 1

我已經創建了一個測試應用程序，並且代碼在下面，並且工作正常...

// CPP code

typedef struct
{
    int ID; 
    char Name[20];
    double value;
    void *Pointer;
    int time;
}InfoStruct;

int WINAPI ModifyListOfControls(InfoStruct *pInfo, int size, bool flag)
{

    int temp = 10;
    pInfo->ID = 10;
    strcpy(pInfo->Name,"Hi");
    pInfo->value = 20.23;
    pInfo->Pointer = (void *)&temp;
    pInfo->time = 50;
    return 0;
}
/***************************************************/
// This is C# code
[StructLayout(LayoutKind.Sequential)]
public struct InfoStruct
{
    public Int32 ID;
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 20)]
    public string Name;
    public Double value;
    public IntPtr Pointer;
    public Int32 time;
};


[DllImport(@"D:\Test\Projects\Release_Build\WeldDll.dll", CallingConvention = CallingConvention.Winapi)]
public static extern int ModifyListOfControls(ref InfoStruct pInfo, int size, bool flag);// ref InfoStruct pi);

public static void Main()
{
    InfoStruct temp = new InfoStruct();

    temp.Pointer = new IntPtr();

    ModifyListOfControls(ref temp, 200, true);

    Console.WriteLine(temp.ID);
    Console.WriteLine(temp.Name);
    Console.WriteLine(temp.time);
    Console.WriteLine(temp.value);


    Console.ReadLine();
}

/ * ** * ** 輸出 * ** * ** * * 10高50 20.23 * ** * ** * ** * ** * ** * ** * * * /