Hi readers,

If I have a structure called sHisto:
STRUCT
History: ARRAY [1..64] OF REAL:
MaxValue: REAL;
MinValue: REAL;
AvgValue: REAL;
END_STRUCT

And I pass it to a functionblock as a pointer:
Measurement: POINTER TO sHisto;

How do I reference the members inside a functionblock? Is the following right?
Measurement.History[3] := 1.0; //set a single array value
temp := Measurement.History[3]^ ; //get a single array value
Measurement.MaxValue := 5.0; //set a member variable
temp := Measurement.MaxValue^; //get a member variable

SomePointerToReal := ADR(Measurement.MaxValue); //pass the addr of a value
SomePointerToRealArr := ADR(Measurement.History); //pass the address of an array
SomePointerTosHisto := (Measurement); //Pass the address of the structure

Best regards,

Someone will correct me if i'm wrong but when you use a pointer and want to access the values directly you need to de-reference it by using the ^. The de-reference comes after the variable pointer name and before the struct member.

So to access a pointer inside the FB you would use:
Measurement^.History[3] := 1.0; //set a single array value
temp := Measurement^.History[3] ; //get a single array value
Measurement^.MaxValue := 5.0; //set a member variable
temp := Measurement^.MaxValue; //get a member variable

If you are trying to pass the addr of a value while still in the FB you wouldn't need the ADR() since it is already referenced as a pointer. Otherwise you are passing an address of an address.
SomePointerToReal := Measurement.MaxValue; //pass the addr of a value
SomePointerToRealArr := Measurement.History; //pass the address of an array
SomePointerTosHisto := Measurement; //Pass the address of the structure

Hello,
I would like to save some values in a structure named Test
The structures is

TYPE test :
STRUCT
generalinfo :general; // 2 variables as string
testfreatures : freatures; // 2 variables as string
END_STRUCT
END_TYPE

I'm using a pointer to the struct test
VAR
INIValues1 : POINTER TO ARRAY [0..1000] OF STRING;
END_VAR
INIValues1 := ADR(Test);
// I want to write the values as follow
INIvalues1^[0].^[0] := 'Test';

How can I mange to do this... I would like later only to replace the struct so my function fits for many different structures

To achieve what you want, you do not declare a "POINTER TO ARRAY[] OF STRING". You declare a "POINTER TO STRING". You can use the array subscript notation directly with this pointer. The array subscript notation performs dereferencing, just like using "^". In fact, ptr[0] and ptr^ are equivalent as far as I can tell.

PROGRAM MAIN
VAR
  INIValues1 : ARRAY [0..1000] OF STRING;
  INIValues1_ptr : POINTER TO STRING;
END_VAR

INIValues1_ptr := ADR(INIValues1);
INIValues1_ptr[0] := 'Test';

Thannk you fajean i replied to you in the folllowing link https://forge.codesys.com/forge/talk/Engineering/thread/b64911d912/?limit=25#0c0f