Check for a Registry Key

Author: Vytautas (talk, contrib)

Description

Include this macro to check to see if a specified registry key exists. After using this macro the stack contains 0 if the key was not present and 1 if it was.

Note: You can also check the error flag after reading the default value of the registry key to know whether the key exits, that is easier in most situations.

[UPDATE: 2004-04-07]

Fixed another typo.

[UPDATE: 2003-11-14]

Fixed a typo in latest version.

[UPDATE: 2003-11-12]

Added Indexed labels to the macro to enable easier modification if needed.

Usage

!insertmacro IfKeyExists "ROOT" "KeyToCheckIn" "KeyToCheck"
Pop $R0
;$R0 contains 0 (not present) or 1 (present)

The Macro

!macro IfKeyExists ROOT MAIN_KEY KEY
push $R0
push $R1
 
!define Index 'Line${__LINE__}'
 
StrCpy $R1 "0"
 
"${Index}-Loop:"
; Check for Key
EnumRegKey $R0 ${ROOT} "${MAIN_KEY}" "$R1"
StrCmp $R0 "" "${Index}-False"
  IntOp $R1 $R1 + 1
  StrCmp $R0 "${KEY}" "${Index}-True" "${Index}-Loop"
 
"${Index}-True:"
;Return 1 if found
push "1"
goto "${Index}-End"
 
"${Index}-False:"
;Return 0 if not found
push "0"
goto "${Index}-End"
 
"${Index}-End:"
!undef Index
exch 2
pop $R0
pop $R1
!macroend

This page was created due to this thread.

Vytautas