byRef - a Better Explanation

[JohnBailey]

Could anyone please clarify what ByRef means? I read and reread the documentation on it. I may be a bit slow , but I'd really like to understand this "attribute" and not just use it.

Documentation

The ByRef keyword is optional and means: (1) the parameter must a variable, and (2) the original variable is linked to the parameter, so that any changes to the parameter inside the function, would affect the original variable as well. By default, a parameter is passed by value which means that a copy of the parameter's value, is manipulated by the function.

The order of the ByRef and Const keywords is not important, so long as they are in front of the variable they modify.

[CoePSX]

It means "By Reference".

You can pass a variable to a function by reference, it's like using pointers.

Let's say you have a variable called $var and a function called IncrementFunction which increments a variable. If you do:

$var = 0
$var2 = IncrementFunction ($var)

MsgBox (0, "DEBUG", $var & " -> " & $var2)

Func IncrementFunction ($number)
    $number = $number + 1
    Return $number
EndFuncoÝ÷ ÚØ^Mú½ªöÈ(v{V§wMú½ªâ²
'¦ÞÑ·j붺w-â²·z+â¯j[Z½ªâi¹^ëbØb±Æ¬y«­¢+ØÀÌØíÙÈôÀ(ÀÌØíÙÈÈô%¹Éµ¹Ñչѥ½¸ ÀÌØíÙȤ()5Í   ½à À°ÅÕ½Ðí UÅÕ½Ðì°ÀÌØíÙȵÀìÅÕ½Ðì´ÐìÅÕ½ÐìµÀìÀÌØíÙÈȤ()Õ¹%¹Éµ¹Ñչѥ½¸¡  åIÀÌØí¹ÕµÈ¤(ÀÌØí¹ÕµÈôÀÌØí¹ÕµÈ¬Ä(IÑÕɸÀÌØí¹ÕµÈ)¹Õ¹

$var2 AND $var1 are going to be 1, because the function received $var by reference. It means the function modified $var itself rather than a copied value.