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Passing a C # double array in C ++ - function using CLI

That's right, what you need sounds simple, but it turns out to be a real pain.

I have GUI code in C # (note that I have never used C # before, but was familiar with the syntax), and I have C ++ code that interacts with it using the CLI .

In C #, I want to create an array of doubles and send it to my C ++ code. I use the code below as a means of transmitting an array, and this runs in isolation.

So, from C # im passing into the double [] array to this function.

public ref class KernelWrapper
{
public: 
    static void ImageNoiseFilter(System::IntPtr imageData, int imageWidth, int imageHeight, array<double>^ values);

What type of parameter should be used to extract this array from C ++?

I tried:

 MyFunction(double values[]){}
 MyFunction(double* values){}
 MyFunction(array<double>^ values){}

, " " ,

Error   1   error C2664: 'RunImageNoiseFilterKernel' : cannot convert parameter 4 from 'cli::array<Type> ^' to 'double *'

, , .

.cpp :

void Bangor::KernelWrapper::ImageNoiseFilter(System::IntPtr imageData, int imageWidth,    int imageHeight, pin_ptr<double> pval){
    RunImageNoiseFilterKernel((Format24bppRgb*)((int)imageData), imageWidth, imageHeight); //If parameter would work, 4th argument would also be passed into this.
}

#:

    double[] randomValues = new double[ARRAY_LENGTH]; //Array of random numbers
    KernelWrapper.ImageNoiseFilter(ptr, image.Width, image.Height, randomValues);

:

Error   1   error C3824: 'cli::pin_ptr<Type>': this type cannot appear in this context (function parameter, return type, or a static member)
Error   3   The best overloaded method match for 'Bangor.KernelWrapper.ImageNoiseFilter(System.IntPtr, int, int, double*)' has some invalid arguments   
Error   4   Argument 4: cannot convert from 'double[]' to 'double*'

, .

+5
2

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using System.Runtime.InteropServices;
using System.Windows.Forms;
using System.Linq;

# :

    float[] randomValues = new float[ARRAY_LENGTH]; //Array of random numbers
    GCHandle handle = GCHandle.Alloc(randomValues, GCHandleType.Pinned);
    var randPtr = handle.AddrOfPinnedObject();
    KernelWrapper.ImageNoiseFilter(ptr, image.Width, image.Height, randPtr);

ImageNoiseFilter:

static void ImageNoiseFilter(System::IntPtr imageData, int imageWidth, int imageHeight, System::IntPtr randValPtr);

++, float, :

void KernelWrapper::ImageNoiseFilter(System::IntPtr imageData, int imageWidth, int imageHeight, System::IntPtr randValues){
    RunImageNoiseFilterKernel((Format24bppRgb*)((int)imageData), imageWidth, imageHeight, (float*) ((int) randValues));
}

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+2

pin_ptr < > class, double *. , , .

#include <vcclr.h>                 // Declares cli::pin_ptr<>
using namespace cli;
#pragma managed(push, off)
#  include "unmanagedstuff.h"      // Declaration of MyFunction here
#pragma managed(pop)

...

        pin_ptr<double> pvalues = &values[0];
        MyFunction(pvalues, values->Length);

, , , MyFunction() , , . , . , , pvalues ​​- , , MyFunction() . , .

+3

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