Re: Passing arrays ByVal vs ByRef

In the clouds?

Cor

"Scott M." <s-mar@xxxxxxxxxxxxx> wrote in message news:%23FeyYxUtJHA.5652@xxxxxxxxxxxxxxxxxxxxxxx
No Cor. With ByRef, you don't get a copy of anything, you get a reference to the variable on the stack that points to the object on the heap.


"Cor Ligthert[MVP]" <Notmyfirstname@xxxxxxxxx> wrote in message news:eXaDvLLtJHA.2776@xxxxxxxxxxxxxxxxxxxxxxx
ByRef references a copy of the value (which is a reference in the case of an array)


"Schizoid Man" <schizoid_man@xxxxxxxxxx> wrote in message news:eGmhn4KtJHA.4140@xxxxxxxxxxxxxxxxxxxxxxx


"Scott M." <s-mar@xxxxxxxxxxxxx> wrote in message news:#T3vJ0JtJHA.4324@xxxxxxxxxxxxxxxxxxxxxxx
This is indeed correct.

When you pass something ByVal, you will get a copy, but most people assume you get a copy of the data, which is not always the case.

What you get a copy of depends on the type you are passing. If you pass a reference type (such as an Array), you get a copy of the reference (the variable pointer), not the type (the Array) and this explains why your original array is modified when you modify the passed parameter.

When you pass a value type ByVal, you get a copy of the value (the data).

-Scott

Thanks for the information, Scott. I was misled a bit, because the method I was invoking was declared as:
Public Shared Function(ByVal InputArray() as Double) as Double

So I just assumed that the array that I was passing was using pass-by-value. If I understand correctly, regardless of the usage of ByVal or ByRef, arrays will *always* be pass-by-reference?

Thanks.




.

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