Difference between ByVal and ByRef?

Question

What is the difference? I always use ByVal, but, I don\'t really have a good idea of when should I and when not...

Answer 1

If you pass in a reference, when you modify the value in the method, the variable in the call site will also be modified.

If you pass value, it's the same as if another variable is created at the method, so even if you modify it, the original variable (at the call site) won't have its value changed.

So, indeed, you should usually pass variables as value. Only pass as reference if you have an explicit need to do so.

Answer 2

ByRef, one value will have 2 addresses

So if x=80 (80 is value and x is address, then for example variable y can be 80 as well, and thus 80 can be accessed by x and y)

Answer 3

I hope this answers your question

Sub last_column_process()
Dim last_column As Integer

last_column = 234
MsgBox last_column

trying_byref x:=last_column
MsgBox last_column

trying_byval v:=last_column
MsgBox last_column

End Sub

Sub trying_byref(ByRef x)
x = 345
End Sub

Sub trying_byval(ByRef v)
v = 555
End Sub