Question

我在C ++中有以下实现（已经创建了相同的DLL）

double *getData()
{
    double *eyeTrackData = new double[10];
    const unique_ptr<Fove::IFVRHeadset> headset{ Fove::GetFVRHeadset() };

    CheckError(headset->Initialise(Fove::EFVR_ClientCapabilities::Gaze), 
"Initialise");

    Fove::SFVR_GazeVector leftGaze, rightGaze;
    const Fove::EFVR_ErrorCode error = headset->GetGazeVectors(&leftGaze, 
    &rightGaze);


    // Check for error
    switch (error)
    {

    case Fove::EFVR_ErrorCode::None:
        eyeTrackData[0] = (double)leftGaze.vector.x;
        eyeTrackData[1] = (double)leftGaze.vector.y;
        eyeTrackData[2] = (double)rightGaze.vector.x;
        eyeTrackData[3] = (double)rightGaze.vector.y;
        break;


    default:
        // Less common errors are simply logged with their numeric value
        cerr << "Error #" << EnumToUnderlyingValue(error) << endl;
        break;
    }

    return eyeTrackData;
}

我已经包含了

extern "C"
{
    __declspec(dllexport) double *getData();
}

在头文件中。

我试着用C-sharp接收它。

[DllImport("C:\\Users\\BME 320 - Section 1\\Documents\\Visual Studio 2015\\Projects\\EyeTrackDll\\x64\\Debug\\EyeTrackDll.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern IntPtr eyeData();

但我不知道如何在buttonClick事件中接收数组。

我很感激你的帮助。

Answer 1

根据@DavidHeffernan提示，我将尝试给您一个如何实现目标的示例。请把C＃部分作为伪代码，因为我不是那种语言的专家。

如前所述，我会使用一个结构，只是为了让事情变得更清楚，我认为给一些类型保护是一个好习惯，并且如果不知道如何确定如何为结构添加“size”属性的可能性很多双打都会。在你的情况下，一如既往是4，不需要。

C ++库中的函数：

void getData(double* eyeTrackData)
{
    const unique_ptr<Fove::IFVRHeadset> headset{ Fove::GetFVRHeadset() };

    CheckError(headset->Initialise(Fove::EFVR_ClientCapabilities::Gaze), "Initialise");

    Fove::SFVR_GazeVector leftGaze, rightGaze;
    const Fove::EFVR_ErrorCode error = headset->GetGazeVectors(&leftGaze, &rightGaze);


    // Check for error
    switch (error)
    {

    case Fove::EFVR_ErrorCode::None:
        eyeTrackData[0] = (double)leftGaze.vector.x;
        eyeTrackData[1] = (double)leftGaze.vector.y;
        eyeTrackData[2] = (double)rightGaze.vector.x;
        eyeTrackData[3] = (double)rightGaze.vector.y;
        break;

    default:
        // Less common errors are simply logged with their numeric value
        cerr << "Error #" << EnumToUnderlyingValue(error) << endl;
        break;
    }
}

C＃方：

[DllImport("C:\\Users\\BME 320 - Section 1\\Documents\\Visual Studio 2015\\Projects\\EyeTrackDll\\x64\\Debug\\EyeTrackDll.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern void eyeData(IntPtr); 

private void button1_Click(object sender, EventArgs e) 
{ 
    try 
    { 
        IntPtr ipr = Marshal.AllocHGlobal(4); // Memory blob to pass to the DLL
        eyeData(ipr);
        double[] eyeTrackData = new double[4]; // Your C# data
        Marshal.Copy(ipr, eyeTrackData, 0, 4); // Convert?
    }
    finally 
    { 
        Marshal.FreeHGlobal(ipr); 
    }
}

再次，抱歉我的“坏C＃”xD。希望这会有所帮助。

从C ++（非托管代码）检索数组到C Sharp格式（托管）

1 个答案: