Work with Array from DLL

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Hi,

hopefully it is possible and I am on the right way.

Lets say I have a function within a DLL:

double ReturnArray() {
     double aReturn[2];
     aReturn[0] = 1.34567;
     aReturn[1] = 1.35678;
     return(*aReturn);
}

Now, I would like to work with this array in MQL

double myArr[2] = ReturnArray();
Comment(myArr[0],myArr[1]);

But MetaEditor said while compiling:

     '(' - unexpected token

 

How can I get rid of this issue?

 

thanks in advance 


 
fx_maddin: Hopefully it is possible and I am on the right way.

Lets say I have a function within a DLL:

double ReturnArray() {
     double aReturn[2];
     aReturn[0] = 1.34567;
     aReturn[1] = 1.35678;
     return(*aReturn);
}

Now, I would like to work with this array in MQL

But MetaEditor said while compiling:

double myArr[2] = ReturnArray();
Comment(myArr[0],myArr[1]);

     '(' - unexpected token

  1. The MOMENT your ReturnArray() returns, the aReturn is gone off the stack and your return pointer is BOGUS. (If it was static or global or on the heap, maybe.)
  2. A mql4 function can only return a variable. Not an array.
  3. double myArr[2]; ReturnArray(myArr);
Comment(myArr[0],myArr[1]);
    void ReturnArray(double *aReturn) {
     aReturn[0] = 1.34567;
     aReturn[1] = 1.35678;
     return;
}

 

You can return array as a parameter of the function. I use that with great success. Writing my dlls using delphi but the idea is the same. You send a pointer to an array as a parameter and read the parameter after the function call. 

 

void ReturnArray(double& Arr[2]);
.....................
double MyArray[2]
ReturnArray(MyArray);
Comment(MyArray[0],MyArray[1]);
 

 WHRoeder,

 your code 

double myArr[2]; ReturnArray(myArr);

 gives also error message 

')' - left square parenthesis expected for array

')' - parameter expected

cyberfx.org,

void ReturnArray(double& Arr[2]);

 in Visual C++ 2010 Express said 

error an array reference is not allowed


I'm currently not sure what to do. I am absolutly newbie to C++ 

 

I have solved it this way:

MQL: 

double myArr[2];
if (ChangeMyArr(myArr)==true) {
    Comment(myArr[0],myArr[1]);
}

DLL:

bool ChangeMyArr (double *myArr) {
    myArr[0] = 1.12345;
    myArr[1] = 9.87654;
    return(true); 
}

This works for me

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