windows - How to write an autohotkey script to toggle the Show hidden files and folders setting?

I would like to make use of a hotkey to toggle the Show hidden files and folders setting. I want to use it on both windowsXp and Windows7.

Here is what I got so far:

#h::
RegRead, Showall_Status, HKEY_LOCAL_MACHINE, Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL, CheckedValue, 
If Showall_Status = 0
RegWrite, REG_DWORD, HKEY_LOCAL_MACHINE, Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL, CheckedValue, 1 
Else
RegWrite, REG_DWORD, HKEY_LOCAL_MACHINE, Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden\SHOWALL, CheckedValue, 0
Return

Problem is when I run the script it simply does nothing. Not sure what I am missing.

Answer

Ok, the problem was the regkey, this one works.

;------------------------------------------------------------------------
; Show hidden folders and files in Windows XP
;------------------------------------------------------------------------
; User Key: [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]
; Value Name: Hidden
; Data Type: REG_DWORD (DWORD Value)
; Value Data: (1 = show hidden, 2 = do not show)

    #h::

        RegRead, ShowHidden_Status, HKEY_CURRENT_USER, Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced, Hidden
        if ShowHidden_Status = 2 
        RegWrite, REG_DWORD, HKEY_CURRENT_USER, Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced, Hidden, 1
        Else
        RegWrite, REG_DWORD, HKEY_CURRENT_USER, Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced, Hidden, 2
        WinGetClass, CabinetWClass
        PostMessage, 0x111, 28931,,, A
        Return