Global And Local Variables

[Lakes]

If I make the variable Global then I don`t need to pass the $Pen variable to the Function?

Global $Pen = 0

Func _IncCol()
    $Pen = $Pen + 1
    If $Pen >5 then 
        $Pen = 0
    EndIF
EndFunc

If the variable is local then I need to pass that variable to the function and the result is passed back?

_IncCol($Pen);Pass Var to Function

Func _IncCol($Pen)
    $Pen = $Pen + 1
    If $Pen >5 then 
        $Pen = 0
    EndIF
EndFunc

Thanks!

[Xenobiologist]

HI,

what is the question?

If IncCol(5) = 0 Then 
MsgBox(0,"Bigger") 
Else
MsgBox(0,"Smaller") 
Endif

Func _IncCol($Pen)
    $Pen += 1
    If $Pen >5 then 
        $Pen = 0
    EndIF
       return $Pen 
EndFunc

So long,

Mega

Edited April 23, 2006 by th.meger

[Lakes]

HI,

what is the question?

If IncCol(5) = 0 Then 
MsgBox(0,"Bigger") 
Else
MsgBox(0,"Smaller") 
Endif

Func _IncCol($Pen)
    $Pen += 1
    If $Pen >5 then 
        $Pen = 0
    EndIF
       return $Pen 
EndFunc

So long,

Mega

The question is, am I correct in the way that local and globel variables are used, If you need to use the same variable in a function.

I guess I`m a bit hazy about the use of passing variables to functions here...

[PsaltyDS]

The question is, am I correct in the way that local and globel variables are used, If you need to use the same variable in a function.

I guess I`m a bit hazy about the use of passing variables to functions here...

Read the help file at LOCAL. There is a detailed discussion of Global/Local and using the variables in functions. Perhaps what you are looking for is about the variables passed in the actual function call? If the variable is declared outside any function, you can refer to it inside a function without passing it to the function. If the value is passed to the function, it should have a unique name inside the fuction (assigned when you declared the function).

You can tweak the following demo script to try out various combinations of variables declared outside/inside a function and globaly/localy. There are too many different variations on the theme to describe them all here:

expandcollapse popup

;Test Global/Local variables
Global $G1 = "One"
$G2 = "Two"

_UseGlobal()

_UseLocal($G2)

MsgBox(64, "Results", "After _UseLocal function: " & @CRLF & _
        "$G1 = " & $G1 & @CRLF & _
        "$G2 = " & $G2)

_ChangeGlobal()

MsgBox(64, "Results", "After _ChangeGlobal() function: " & @CRLF & _
        "$G1 = " & $G1 & @CRLF & _
        "$G2 = " & $G2)


; Local Functions

Func _UseGlobal()
    MsgBox(64, "Global", "Global $G1 = " & $G1 & @CRLF & _
            "Global $G2 = " & $G2)
EndFunc  ;==>_UseGlobal

Func _UseLocal($sVar)
    Local $G1 = "Three", $G2 = "Four"
    MsgBox(64, "Local", "Function was passed $sVar = " & $sVar & @CRLF & _
            "Local $G1 = " & $G1 & @CRLF & _
            "Local $G2 = " & $G2)
EndFunc  ;==>_UseLocal

Func _ChangeGlobal()
    $G1 = "Three"
    $G2 = "Four"
    MsgBox(64, "Inside _ChangeGlobal() Function", "$G1 = " & $G1 & @CRLF & _
            "$G2 = " & $G2)
EndFunc  ;==>_ChangeGlobal

Hope that helps...

Edit: Tweaked malformed MsgBox(), added changing the global.

Edited April 24, 2006 by PsaltyDS

[CyberSlug]

If you want a function to change a variable, you either need to use a global variable or pass that variable to a function as ByRef.

Func swap(ByRef $a, ByRef $b)
  Local $temp
  $temp = $a
  $a = $b
  $b = $temp
EndFunc

Otherwise, the parameters are not modified.

Edited April 24, 2006 by CyberSlug

[Lakes]

If you want a function to change a variable, you either need to use a global variable or pass that variable to a function as ByRef.

Func swap(ByRef $a, ByRef $b)
  Local $temp
  $temp = $a
  $a = $b
  $b = $temp
EndFunc

Otherwise, the parameters are not modified.

Thanks Guys, much clearer now.