Using GUICtrlSetState on checkboxes in a for loop

[benjbong]

I have a form that has a number of checkboxes in it that i am trying to create a select all/clear all script for. The checkboxes are defined in variables like

$checkbox1 = GUICtrlCreateCheckbox("Option 1", -1, 0)
$checkbox2 = GUICtrlCreateCheckbox("Option 2", 0, -1)

I have an array with all the names of the checkboxes in it like

dim $Chkboxes[8] = ["checkbox1", "checkbox2", ...]

I want to use a loop to check all the checkboxes using the array to list them. Originally i tried:

For $i = 0 to UBound($Chkboxes) -1 Step 1
$str = "$" & $Chkboxes[$i]
GUICtrlSetState(Eval($str), $GUI_CHECKED)
Next

Which didn't work. I also tried String($str) which would print correctly in a message box, but wouldn't work in the setstate function. I changed my code to this:

For $i = 0 to UBound($Chkboxes) -1 Step 1
GUICtrlSetState(Eval($Chkboxes[$i]), $GUI_CHECKED)
Next

Which works. I'm excited that it works - i just want to know WHY. Because if i print the eval($Chkboxes[$i]) in a message box it shows me incrementing numbers. I want to know what exactly is happening here so i can apply this to other situations, rather than just having this one working.

[BrewManNH]

Why not assign the checkboxes to an array and loop through the array to check/uncheck the checkboxes instead of trying to loop through a load of variable name?

[benjbong]

You mean define the checkboxes as the elements in the array rather than creating the checkboxes and then creating an array that points at them? how would i go about doing that? Sorry - i'm extremely new to autoit, not programming though.

[BrewManNH]

Instead of this:

$checkbox1 = GUICtrlCreateCheckbox("Option 1", -1, 0)
$checkbox2 = GUICtrlCreateCheckbox("Option 2", 0, -1)

Try this:

For $I = 0 to 1
     $checkbox[$i] = GUICtrlCreateCheckbox("Option " & $i, -1, 0)
Next

[benjbong]

Thanks, that idea worked well. I ended up using a similar approach but rather than using the "option " & $i piece i used the elements of another array to populate the data field.