[thelist] byref vs. byval clarification (was [Off-topic] --ta boo!)

Scott Dexter sgd at ti3.com
Fri Mar 16 17:50:07 CST 2001

> Can you tell sgd uses frontpage? He didn't close his tip tag...

oops, sorry kids

> Ok, here's a question:
> function Yo(aNumber)
>     anotherNumber = aNumber
>     anotherNumber = 14
>     Yo = true
> end function
> x = 1
> good = Yo(x)
> when this occurs in the function:
>     anotherNumber = aNumber
> is the reference assigned, or the value? In other words, does 
> x=1 or does
> x=14?

Since Matt was too lazy to actually try it, I did. The code:

function addme(x1,y1)
temp = x1
temp2 = y1
temp = 14
addme = temp+temp2
end function
Response.Write "x before:"&x&"<BR>"
total = addme(x,y)
Response.Write "x after:"&x&"<br>"

the results:
x before:1
x after:1

So, the assignment is a copy. But this is with a scalar. I've watched
behavior of ADO Recordsets (and the Request collection and CapRock's
Dictionary object) where the assignment *is* the reference, unless you throw
CStr() around it to make it a copy.

something to be aware of, and unless you want to affect the original
variable, get in the habit of typing "byval" in your procedure parameter


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