Passing multi parameter array to a C++ DLL

#define MYDLL_EXPORT comment(linker, "/EXPORT:"__FUNCTION__"="__FUNCDNAME__)
 
 
int WINAPI ArrayTestingFunction(double testArray[][10]) {
 
     double value = testArray[1][1];
 
     // Change the value in  the array and check for the new value in the calling EA
     testArray[1][1] = value * 2;
 
     return(0);
     #pragma MYDLL_EXPORT
}

Quoting skinner36

Disliked

...

Ignored

 
#define MYDLL_EXPORT comment(linker, "/EXPORT:"__FUNCTION__"="__FUNCDNAME__)
 
void WINAPI ArrayTestingFunction(double testArray[][10]);
 
void WINAPI ArrayTestingFunction(double testArray[][10]) {
 
     double value = testArray[1][1];
 
     // Change the value in  the array and check for the new value in the calling EA
     testArray[1][1] = value * 2;
 
     //return(0);
     #pragma MYDLL_EXPORT
}

#property strict
 
#import "ArrayTest.dll"
    void ArrayTestingFunction(double &testArray[][10]);
#import
 
  
int OnInit()
{
    double testArray[][10];
        
    ArrayResize(testArray,10);
    // Give an element a test value
    testArray[1][1] = 5;
    // Call the DLL with the array
    ArrayTestingFunction(testArray);
    // Check the array element to see if we can see how it was modified in the DLL
    Alert(testArray[1][1]);
    return(INIT_SUCCEEDED);
}

#include "stdafx.h"
 
#define MYDLL_EXPORT comment(linker, "/EXPORT:"__FUNCTION__"="__FUNCDNAME__)
 
void WINAPI ArrayTestingFunction(double testArray[][10]);
 
void WINAPI ArrayTestingFunction(double testArray[][10]) {
 
     double value = testArray[1][1];
 
     // Change the value in  the array and check for the new value in the calling EA
     testArray[1][1] = value * 2;
 
     //return(0);
     #pragma MYDLL_EXPORT
}

Quoting skinner36

Disliked

...why would the function work when I pass a single dimension array but fail when I pass a multi dimension array...

Ignored

Quoting skinner36

Disliked

!!!!!!!!!!!!! BINGO - It is working !!!!!!!!!!!!!!!!!!!!!!

Ignored

Quoting skinner36

Disliked

...Would this information be more correct to put into a def file then rather than put it into [...] the project...

Ignored

Quoting skinner36

Disliked

...I was playing around with passing an array of structs from MQL and using it as a vector in C++ as a more descriptive way of doing things. Do you think this is possible...

Ignored

// double testArray[10][12];
double testArray[800000][12];
ArrayTestingFunction(testArray);
Alert(testArray[1][1]);

void WINAPI ArrayTestingFunction(double testArray[][12]) {
 
double value = testArray[1][1];
 
// Change the value in  the array and check for the new value in the calling EA
testArray[1][1] = value * 2;
 
//return(0);
#pragma MYDLL_EXPORT
}

Quoting skinner36

Disliked

...as soon as the dll is called I get a corrupt stack error because of the new large array size...

Ignored

Quoting skinner36

Disliked

My thoughts were to try to pass a pointer to an array of struct but so far it is generating an error. Does anyone know if this is possible?

Ignored

#pragma pack(push,1)
struct BinData
{ int Number;
     double Amplitude;
     int Frequency;
};
#pragma pack(pop)

Quoting skinner36

Disliked

Hi, Sometimes it would be very useful to use the same data between mql programs. I know that we can use global variables but that is only for a single double value. What if we wanted to access an array of double values. Is there any way that we could create an array in an EA and pass it to a dll, have the dll procees the array and then an indicator pick up the address of the pointer and access the same array? I am just trying to think outside the box here. Cheers, John

Ignored

Quoting mladen

Disliked

{quote} What is preventing you to pass the array by reference to a dll and use it as you want?

Ignored