View source for Event Compile.GetVarSize

{| class="wikitable" style="width:60%; background-color:#FFFFFF;"
|-
| width="10%" align="center" style="background-color:#D8C9D8;" align="center" | [[File:Fc9-comp-macro.png]]
| width="90%" style="background-color:#D8C9D8; color:#4B008D;" | '''GetVarSize'''
|-
| colspan="2" | Sent to a component to amend the size of the expected array&nbsp;
|-
|-
| width="10%" align="center" | [[File:Fc9-string-icon.png]] - STRING
| width="90%" | VarName
|-
| colspan="2" | The original Flowcode variable&nbsp;
|-
| width="10%" align="center" | [[File:Fc9-u32-icon.png]] - ULONG
| width="90%" | Elements
|-
| colspan="2" | The number of elements in the array&nbsp;
|-
| width="10%" align="center" style="border-top: 2px solid #000;" | [[File:Fc9-void-icon.png]] - NONE
| width="90%" style="border-top: 2px solid #000;" | ''Return''
|}


Details on using Event Macros can be found here: [[Simulation Events|Event Macros]]


==Detailed description==



==Examples==

On some microcontroller devices there are sometimes limitation on the size of a single data array or other reasons to adjust the size of a variable based on a set of parameters etc.


For example if we try and create an array of size bigger then 256 bytes then this will cause a compilation error.



'''#define FCVsz_DATAARRAY 500'''



'''GetVarSize.c(53): error: total number of array elements can not exceed 0x100'''



By enabling the GetVarSizeevent we can override the number of elements in the array.


[[File:GetVarSizeEvent.jpg]]


Inside the event macro we check for the name of the variable with the size we want to override and overwrite the .Elements local variable to edit the array size.


[[File:GetVarSizeMacro.jpg]]


After saving the project and refreshing the C code window the variable now looks like this.



'''#define FCVsz_DATAARRAY 255'''



And during compilation we now get this.



'''success'''



Here is the file as a demonstration. 

{{Fcfile|GetVarSize.fcfx|Get Var Size Event Example}}