build a variable name dynamicly

All,

I'm new at this forum ans also to AutoIt, so don't shoot me when i'm asking something that's evident.

I'm looking for the correct way to build a variabele name.

i have a gui with 22 buttons. Every button has i'ts one settings.
depending on the input from an ini file, i need to set the focus on that button.

This is my code

ini file ==>
[ButtonId]
button=15

code ==>
$ButtonId = IniRead("C:\Temp\myfile.ini", "ButtonId", "Button")

$button14=GuiCtrlCreateButton("test 14",130,410,100,50)

$button15=GuiCtrlCreateButton("Test 15",240,410,100,50)
$button16=GuiCtrlCreateButton("Test 16",350,410,100,50)

GUICtrlSetState($button & ButtonId, $GUI_FOCUS)

but the last line doesn't work :-(

kind regards