LINKED LIST

[jruelan 0]

can autoit do linked list? and OOP?

[weaponx 10]

You could fake it (maybe):

$string = "char firstname[128];char lastname[128];ptr next"

$head = DllStructCreate ($string)

DllStructSetData($head,1,"John")

DllStructSetData($head,2,"Smith")

DllStructSetData($head,3,"")

$headPtr = DllStructGetPtr ( $head)

$firstElement = DllStructCreate ($string)

DllStructSetData($firstElement,1,"John")

DllStructSetData($firstElement,2,"Smith")

DllStructSetData($firstElement,3,"")

DllStructSetData($head,3,DllStructGetPtr ($firstElement))

EDIT - changed last line

Edited October 11, 2007 by weaponx

[SkinnyWhiteGuy 2]

You could fake it (maybe):

$string = "char firstname[128];char lastname[128];ptr next"

$head = DllStructCreate($string)

DllStructSetData($head,1,"John")

DllStructSetData($head,2,"Smith")

DllStructSetData($head,3,"")

$headPtr = DllStructGetPtr($head)

$firstElement = DllStructCreate($string)

DllStructSetData($firstElement,1,"John")

DllStructSetData($firstElement,2,"Smith")

DllStructSetData($firstElement,3,"")

DllStructSetData($head,2,DllStructGetPtr($firstElement))

I think you meant that last line to be

DllStructSetData($head,3,DllStructGetPtr($firstElement))

Otherwise, the first John Smith no longer has a last name.

Edit: As to OOP, that is not currently supported, see here.

Edited October 11, 2007 by SkinnyWhiteGuy

[weaponx 10]

The problem with the above code is that in order to loop through a linked list you need to be able to read a structure by it's pointer, and although you can get a structures pointer, the DllStructGetData() function uses the handle of the structure to read from it and not the pointer.

Someone correct me if i'm wrong.

So i guess instead of storing a pointer to the next element perhaps you could store the autoit handle of the structure?

I tried this code below but I don't know what datatype the Autoit structure handle is so it doesn't work as expected:

;$string = "char firstname[128];char lastname[128];ptr next"

$string = "char firstname[128];char lastname[128];hwnd next"

$head = DllStructCreate ($string)

DllStructSetData($head,1,"John")
DllStructSetData($head,2,"Smith")
DllStructSetData($head,3,"")

;$headPtr = DllStructGetPtr ( $head)

$firstElement = DllStructCreate ($string)

DllStructSetData($firstElement,1,"Steve")
DllStructSetData($firstElement,2,"Jones")
DllStructSetData($firstElement,3,"")

;Assign next pointer by actual pointer
;DllStructSetData($head,3,DllStructGetPtr ($firstElement))

;Assign next pointer by autoit handle
DllStructSetData($head,3,$firstElement)

;Expecting: Steve
;Actual: 0
MsgBox(0,"",DllStructGetData(DllStructGetData($head,3),1))

;Display all elements
$nodePtr = $head
While $nodePtr <> ""
    ;Get next element
    MsgBox(0,"",DllStructGetData($nodePtr,1))
    $nodePtr = DllStructGetData($nodePtr,3)
WEnd

[weaponx 10]

Does anyone know if there is a way to store the handle from DllStructCreate() in an already created structure? (i.e. what datatype is the internal AutoIt handle)

- or -

How can you use DllStructGetData() if you only have a pointer to a previously created structure?

[weaponx 10]

Here is a working example of a linked list. I'm not sure how well it performs though. I thought I read somewhere that DllStruct* commands can be much slower than reading from an array for example. Credit goes to Valik for pointing out the mistakes in the previous post.

Local $string = "char firstname[128];char lastname[128];ptr next"

Local $head = DllStructCreate ($string)
Local $headPtr = DllStructGetPtr ( $head)

DllStructSetData($head,1,"First Name 1")
DllStructSetData($head,2,"Last Name 1")
DllStructSetData($head,3,0)

Local $firstElement = DllStructCreate ($string)

DllStructSetData($head, 3, DllStructGetPtr($firstElement))

DllStructSetData($firstElement,1,"First Name 2")
DllStructSetData($firstElement,2,"Last Name 2")
DllStructSetData($firstElement,3,0)

Local $pNext = $headPtr
While $pNext <> 0
    Local $current = DllStructCreate($string, $pNext)
    ConsoleWrite(DllStructGetData($current, 1) & @CRLF)
    ConsoleWrite(DllStructGetData($current, 2) & @CRLF)
    $pNext = DllStructGetData($current, 3)
WEnd