[Gambas-user] Structure array, at second reading, always gives the value of the last element

[vuott at tiscali.it]

Oooh yes, you are right. 
I knew this procedure, but I have
forgotten it totally. 
thanks 

Il 06.08.2019 14:32 ML ha scritto: 

>
On 6/8/19 08:05, vuott at tiscali.it [1] wrote:
> 
>> Hello, 
>> I don't
understand why at the second reading of a Structure array I always get
the value of the last element. 
>> 
>> Public Struct AAAA b As Byte c As
Short i As Integer End Struct Public Sub Main() Dim a As New AAAA Dim aa
As New AAAA[] Dim i As Integer For i = 0 To 7 aa.Push(a) Valorizza(i,
aa[i]) Print aa[i].b, ' first Next Print Print For i = 0 To 7 Print
aa[i].b, ' second Next End Private Procedure Valorizza(c As Integer, s
As AAAA) s.b = 4 * c End
> Looks like all the structs in the array refer
(i.e: they're pointers) to the same 'a' struct in the first DIM.
>
Therefore, when you change the value in ANY element, you end up changing
it in all elements just because they're all pointing to the same
original 'a'.
> 
> Change the first DIM to this:
> 
> Dim a As AAAA 
>
and alter the first FOR as follows:
> 
> For i = 0 To 7 a = New AAAA
'New line. This makes 'a' point to a new, different structure in memory
in each pass aa.Push(a) 'continue your original code here 
> That fixes
it.
> 
> zxMarce.
  


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