create a new variable inside an If statement?

[frew]

Hello,

Why does $y3 = $y2 - 100 not create the variable $y3 in the If statement below?

Variable not declared error comes about apparently because I try to create a new variable

inside an If statement, like this, for example:

If $y2 < $y1 Then
    $y3 = $y2 - 100   ;this does not create the variable $y3 as I thought it would
EndIf

If $y3 > 716 Then   ;error says that this variable is trying to be used without being declared
    $y3 = 716
EndIf

Solution: I put

Dim $y3

at the top of the script. (but I didn't think that was supposed to be necessary, because generally I have been able to

just create variables as I go along anywhere in the script.)

Thanks for any ideas about this.

frew

Edited April 27, 2009 by frew

[Valuater]

Maybe because it is not ABSOLUTE that $y2 < $y1. If not then the next If/test is invalid because $y3 was never created

8)

[frew]

Maybe because it is not ABSOLUTE that $y2 < $y1. If not then the next If/test is invalid because $y3 was never created

Ah, yes...thank you Valuater, that makes sense.

I guess then it's a good rule of thumb to not try to create variables inside If statements.

Okay, if I do If statements like this, I guess I just have to be sure to declare any variables that may be created inside the Ifs

outside the Ifs. Like with a Dim above the If statement.

Thank you very much,

frew

[Valuater]

Welcome!

As I understand it is better to use Global rather than Dim per Dev's here.... and remember to use Local rather than Global for example inside a function.

8)

Edited April 27, 2009 by Valuater

[frew]

As I understand it is better to use Global rather than Dim per Dev's here.... and remember to use Local rather than Global for example inside a function.

That's good to know, thanks.

I see so much Dim around in much code examples, I thought maybe that was the way to go.

Okay, Global and Local...Global for when a variable's value is the same throughout the script, and Local for when the variable's value may change throughout the script...I think that's the idea.

I'll study that in the help I guess...because I may be mixing that up with Constants, sorry.

Thanks, I'll look into that.

frew

[Valuater]

You are mixing them slightly . so yea, have a look in the help file, it's pretty good!!

8)