Re: Passing arrays ByVal vs ByRef



"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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