I created an empty function block called MyObject, then declared an array of instances of the function block, as such:

MyArray : ARRAY [1..2] OF MyObject;

So far, so good. Now I add an FB_Init method to MyObject:

METHOD FB_Init : Bool
VAR_INPUT
  bInitRetains : BOOL; // if TRUE, the retain variables are initialized (warm start / cold start)
  bInCopyCode : BOOL;  // if TRUE, the instance afterwards gets moved into the copy code (online change)
  ID : UINT;
END_VAR

The question is, how do I now declare an array of MyObject? My original declaration doesn't work any more because the objects can't be created without the 'ID' parameter. But I can't figure out any way to pass it in. I was hoping something along the lines of this would work:

MyArray : ARRAY [1..2] OF MyObject := [ (ID:=24), (ID:=17) ];

but that doesn't compile.

Any suggestions on how to do this?

Originally created by: scott_cunningham

I have found adding VAR_INPUTS to Fb_init() to be a little troubling - intellisense doesn't show the VAR_INPUTS, so there are no hints to the user. Also, an unfriendly error "No matching FB_init method found for instantiation...". So, I normally just create my own "init" method that I call during first boot and initialize necessary items. A bit of a workaround, but also very clear what is happening to other programmers:

FUNCTION_BLOCK MyObject
METHOD MyInit
VAR_INPUT
   ID: UINT;
END_VAR
...
END_METHOD
PROGRAM PLC_PRG
VAR
   MyArray: ARRAY[1..2] OF MyObject;
   FirstBoot: BOOL:= TRUE;
END_VAR
IF FirstBoot THEN
   MyArray[1].MyInit(ID:= 24);
   MyArray[2].MyInit(ID:= 17);
   ...
   FirstBoot:= FALSE;
END_IF
...
END_PROGRAM

get rid of this:

:=

FB_init is a method/funciton and needs to be called! not assigned...

Do it like the following:

MyArray : ARRAY [1..2] OF MyObject[ (ID:=24), (ID:=17) ];

Then intellisense works at least at the first line though