registry access functions

This code has been declared by its author to be Public Domain code.

registry access functions by gman

2004

a small library implementing some functions and constants that work with the windows registry.

** NOTES **
- messing with your registry can really muck with your machine so use at your own risk.
- this library requires advapi32.dll decls for registry access in your userlibs folder.
- supports REG_SZ, REG_DWORD, and REG_BINARY types
- any errors that occur are stored in a global variable called "reg_lasterr"

functions:
reg_openkey - opens a registry key and returns the handle
reg_closekey - closes a registry key opened with reg_openkey or reg_createkey
reg_createkey - creates a key if it doesnt exist and opens it, returning the handle
reg_deletekey - deletes a key from the registry
reg_setvalue - stores a value in the registry
reg_getvalue - returns a value from the registry as a string. can optionally return a delimited string with the data type preceding the value.
reg_deletevalue - deletes a value from the registry
reg_enumkeys - returns a delimited string of the keys contained under the passed key.
reg_enumvalues - returns a delimited string containing stored values (both name and value). can optionally return type preceding the name.

a few use examples (written in B+):

i find it good to define a constant housing your application root.

Const REG_APPROOT$ = "SOFTWARE\My Application"

test to see if a key exists

If Not reg_iskey(HKEY_LOCAL_MACHINE,REG_APPROOT$)
	Notify("reg_iskey: Application Key Does Not Exist")
EndIf

try to open a key

hKey=reg_openkey(HKEY_LOCAL_MACHINE,REG_APPROOT$)
If hKey<>-1
	Notify("reg_openkey: Key opened, returned handle "+hKey)
	reg_closekey(hKey)
Else
	Notify("reg_openkey: Application Key Does Not Exist")
EndIf

create a key and open it or open if it exists

hKey=reg_createkey(HKEY_LOCAL_MACHINE,REG_APPROOT$)
If hKey<>-1
	Notify("reg_createkey: Key created, returned handle "+hKey)
	reg_closekey(hKey)
Else
	Notify("reg_createkey: Key creation failed, check req_lasterr.")
EndIf

set some values

; string
reg_setvalue(HKEY_LOCAL_MACHINE,REG_APPROOT$,"test1","1212")
; integer
reg_setvalue(HKEY_LOCAL_MACHINE,REG_APPROOT$,"test2",3344,REG_DWORD)

get the values

Notify("test1: "+reg_getvalue(HKEY_LOCAL_MACHINE,REG_APPROOT$,"test1"))
Notify("test2 with type prepended: "+reg_getvalue(HKEY_LOCAL_MACHINE,REG_APPROOT$,"test2","",True))

enumeration of values

; without type
Notify(reg_enumvalues(HKEY_LOCAL_MACHINE,REG_APPROOT$))
; with type prepended
Notify(reg_enumvalues(HKEY_LOCAL_MACHINE,REG_APPROOT$,"|",True))

delete a value

reg_deletevalue(HKEY_LOCAL_MACHINE,REG_APPROOT$,"test1")

delete the key

reg_deletekey(HKEY_LOCAL_MACHINE,REG_APPROOT$)

; registry roots
Const HKEY_CLASSES_ROOT			= -2147483648
Const HKEY_CURRENT_USER			= -2147483647
Const HKEY_LOCAL_MACHINE		= -2147483646
Const HKEY_USERS			= -2147483645

; return value constants
Const ERROR_SUCCESS 			= 0
Const ERROR_EOF				= 259  	; no more entries in key

; data types For keys
Const REG_SZ				= 1	; Data String
Const REG_BINARY			= 3	; Binary Data in any form.
Const REG_DWORD				= 4 	; A 32-bit number.

; global var holding last error #
Global reg_lasterr			= ERROR_SUCCESS

; enumerates the keys contained in the passed subkey and returns them as a delimited string in 
; the format: KEY=VALUE|KEY=VALUE|KEY=VALUE
Function reg_enumvalues$(RegKey%,SubKey$,delim$="|",types=False)
	Local cRetVal$="",key$="",val$=""
	Local keybank=CreateBank(100),keybanksize=CreateBank(4),valbank=CreateBank(100),valbanksize=CreateBank(4),typebank=CreateBank(4)
	Local char=0,nIdx=0,nType=0

	; open the key 
	Local hKey=reg_openkey(RegKey,SubKey$)
	If hKey<>-1	
	
		; read in the values
		Repeat
			; init the banks
			PokeInt(typebank,0,0)
			PokeInt(valbanksize,0,100)
			PokeInt(keybanksize,0,100)
		
			; clear out the temp values
			key$=""
			val$=""
			
			If RegEnumValue(hKey,nIdx,keybank,keybanksize,0,typebank,valbank,valbanksize)<>ERROR_EOF
				nType=PeekInt(typebank,0)
				
				; tack on the delimiter
				If cRetVal$<>""
					cRetVal$=cRetVal$+delim$
				EndIf 

				; build the key name
				For char=0 To PeekInt(keybanksize,0)-1
					If PeekByte(keybank,char)=0 Then Exit
					key$=key$+Chr(PeekByte(keybank,char))
				Next

				Select nType
					; read in a string or binary value
					Case REG_SZ, REG_BINARY
						; build the value
						For char=0 To PeekInt(valbanksize,0)-1
							If PeekByte(valbank,char)=0 Then Exit
							val$=val$+Chr(PeekByte(valbank,char))
						Next
					; read in an integer
					Case REG_DWORD
						val$=PeekInt(valbank,0)						
				End Select

				If types
					cRetVal$=(cRetVal$+PeekInt(typebank,0)+";"+key$+"="+val$)
				Else
					cRetVal$=(cRetVal$+key$+"="+val$)
				EndIf
			Else
				Exit
			EndIf			
			
			nIdx=nIdx+1
		Forever
		reg_closekey(hKey)
	EndIf
	
	FreeBank typebank
	FreeBank valbank
	FreeBank valbanksize
	FreeBank keybank
	FreeBank keybanksize
	
	Return cRetVal$
End Function

; enumerates the keys contained in the passed subkey and returns them as a delimited string in 
; the format: KEY|KEY|KEY
Function reg_enumkeys$(RegKey%,SubKey$,delim$="|")
	Local cRetVal$=""
	Local keybank=CreateBank(100)
	Local nIdx=0

	; open the key first	
	Local hKey=reg_openkey(RegKey,SubKey$)
	If hKey<>-1	
		Repeat			
			If RegEnumKey(hKey,nIdx,keybank,BankSize(keybank))<>ERROR_EOF			
				; tack on the delimiter
				If cRetVal$<>""
					cRetVal$=cRetVal$+delim$
				EndIf 
				
				For char=0 To BankSize(keybank)-1
					If PeekByte(keybank,char)=0 Then Exit
					cRetVal$=cRetVal$+Chr(PeekByte(keybank,char))
				Next
			Else
				Exit
			EndIf
			
			nIdx=nIdx+1
		Forever
		reg_closekey(hKey)
	EndIf

	FreeBank keybank
	Return cRetVal$
End Function

; deletes a value from the registry.  returns True/False.
Function reg_deletevalue%(RegKey%,SubKey$,ValueName$)
	Local hKey=reg_openkey(RegKey,SubKey$)
	Local lRetVal=False
	If hKey<>-1
		Local nRslt=RegDeleteValue(hKey,ValueName$)		
		If (nRslt=ERROR_SUCCESS)
			lRetVal=True
		Else
			reg_lasterr=nRslt
		EndIf
		reg_closekey(hKey)
	EndIf
	Return lRetVal
End Function

; gets a value from the registry and returns it as a string.  will return the passed default
; if the value requested is not found in the registry.
Function reg_getvalue$(RegKey%,SubKey$,ValueName$,Dflt$="",types=False)
	Local cRetVal$=Dflt$
	Local hKey=reg_openkey(RegKey,SubKey$)
	Local char=0,nType=0
	
	; open the key 
	If hKey<>-1
		Local valbank=CreateBank(100),valbanksize=CreateBank(4),typebank=CreateBank(4)
	
		; init the banks
		PokeInt(typebank,0,0)
		PokeInt(valbanksize,0,100)
	
		Local nRslt=RegQueryValueEx(hKey,ValueName$,0,typebank,valbank,valbanksize)
		If (nRslt=ERROR_SUCCESS)
			cRetVal$=""
		
			nType=PeekInt(typebank,0)
			
			; build the value
			Select nType
				; read in a string or binary value
				Case REG_SZ, REG_BINARY
					; build the value
					For char=0 To PeekInt(valbanksize,0)-1
						If PeekByte(valbank,char)=0 Then Exit
						cRetVal$=cRetVal$+Chr(PeekByte(valbank,char))
					Next
				; read in an integer
				Case REG_DWORD
					cRetVal$=PeekInt(valbank,0)						
			End Select
			
			; tack on the type if requested
			If types
				cRetVal$=nType+";"+cRetVal$
			EndIf
		Else
			reg_lasterr=nRslt
		EndIf
		reg_closekey(hKey)
	EndIf
	Return cRetVal$
End Function

; sets a value in the registry.  defaults to type string, but can pass REG_DWORD and REG_BINARY.
; returns True/False.
Function reg_setvalue%(RegKey%,SubKey$,ValueName$,Value$,nType=REG_SZ)
	Local hKey=reg_openkey(RegKey,SubKey$)
	Local lRetVal=False
	If hKey<>-1
		Local valbank
		
		; create a bank to hold the info
		Select nType
			Case REG_SZ, REG_BINARY
				valbank=CreateBank(Len(Value$))				
				For i=1 To Len(Value$)
					PokeByte(valbank,i-1,Asc(Mid(Value$,i,1)))
				Next				
			Case REG_DWORD
				valbank=CreateBank(4)
				PokeInt(valbank,0,Int(Value$))
		End Select
	
		Local nRslt=RegSetValueEx(hKey,ValueName$,0,nType,valbank,BankSize(valbank))
		If (nRslt=ERROR_SUCCESS)
			lRetVal=True
		Else
			reg_lasterr=nRslt
		EndIf
		reg_closekey(hKey)
	EndIf
	Return lRetVal
End Function

; deletes the passed key from the registry.  returns True/False.
Function reg_deletekey%(RegKey%,KeyName$)
	reg_lasterr=ERROR_SUCCESS
	Local nRslt=RegDeleteKey(RegKey,KeyName$)
	
	If nRslt<>ERROR_SUCCESS
		reg_lasterr=nRslt
	EndIf
	
	Return (nRslt=ERROR_SUCCESS)
End Function

; returns the registry handle or -1 if failed.
Function reg_createkey%(RegKey%,KeyName$)
	reg_lasterr=ERROR_SUCCESS
	Local regbank=CreateBank(4)
	Local hKey=-1

	Local nRslt=RegCreateKey(RegKey%,KeyName$,regbank)

	If (nRslt=ERROR_SUCCESS)
		hKey=PeekInt(regbank,0)
	Else
		reg_lasterr=nRslt
	EndIf

	FreeBank regbank	
	Return hKey
End Function 

; returns the registry handle or -1 if failed
Function reg_openkey%(RegKey%,KeyName$)
	reg_lasterr=ERROR_SUCCESS
	Local regbank=CreateBank(4)
	Local hKey=-1

	Local nRslt=RegOpenKey(RegKey%,KeyName$,regbank)

	If (nRslt=ERROR_SUCCESS)
		hKey=PeekInt(regbank,0)
	Else
		reg_lasterr=nRslt
	EndIf

	FreeBank regbank
	Return hKey
End Function 

; closes the registry key.  returns True/False.
Function reg_closekey%(RegKey%)
	reg_lasterr=ERROR_SUCCESS
	Local nRslt=RegCloseKey(RegKey)
	
	If nRslt<>ERROR_SUCCESS
		reg_lasterr=nRslt
	EndIf
	
	Return (nRslt=ERROR_SUCCESS)
End Function

; returns true if the key exists
Function reg_iskey%(RegKey%,KeyName$)
	Local hKey=reg_openkey(RegKey,KeyName$)
	Local lRetVal=False

	If hKey<>-1
		reg_closekey(hKey)
		lRetVal=True
	EndIf
	
	Return lRetVal
End Function

Comments

cyberseth

2006

This is a great set of routines, but the reg_deletekey function does not delete registry entries with multiple subkeys (on Windows NT/2000 or above). This can be remedied by putting the following code at the beginning of the reg_deletekey function:

	subkeys$ = reg_enumkeys(RegKey%, KeyName$, Chr(13))
	While Len(subkeys$)>0
		If Instr(subkeys$,Chr(13)) Then
			reg_deletekey(RegKey%, KeyName$+"\"+Left(subkeys$,Instr(subkeys$,Chr(13))-1))
			subkeys$ = Mid(subkeys$,Instr(subkeys$,Chr(13))+1)
		Else
			reg_deletekey(RegKey%, KeyName$+"\"+subkeys$)
			Exit
		End If
	Wend

_PJ_

2009

Cyberseth's correction not ony wont compile, but can cause infinite loops.
A fix that works: (Entire Function here)

; deletes the passed key from the registry.  returns True/False.
Function reg_deletekey%(RegKey%,KeyName$)
	reg_lasterr=ERROR_SUCCESS
	Local nRslt=RegDeleteKey(RegKey,KeyName$)
	
	If nRslt<>ERROR_SUCCESS
		reg_lasterr=nRslt
	EndIf
	
subkeys$ = reg_enumkeys(RegKey%, KeyName$)
	While Len(subkeys$)
		If Instr(subkeys$,Chr(13)) Then
			reg_deletekey(RegKey%, KeyName$+"\"+Left(subkeys$,Instr(subkeys$,Chr(13))-1))
			subkeys$ = Mid(subkeys$,Instr(subkeys$,Chr(13))+1)
		Else
			reg_deletekey(RegKey%, KeyName$+"\"+subkeys$)
			Exit
		End If
	Wend
	Return (nRslt=ERROR_SUCCESS)
End Function

With this additional update to reg_enumkeys (Again, full function here)

; enumerates the keys contained in the passed subkey and returns them as a delimited string in 
; the format: KEY|KEY|KEY
Function reg_enumkeys$(RegKey%,SubKey$,delim$="|")
	Local cRetVal$=""
	Local keybank=CreateBank(100)
	Local nIdx=0
Local ExitLoop%=False

	; open the key first	
	Local hKey=reg_openkey(RegKey,SubKey$)
	If hKey<>-1	
		While (Not(ExitLoop%))			
			If RegEnumKey(hKey,nIdx,keybank,BankSize(keybank))<>ERROR_EOF			
				; tack on the delimiter
				If cRetVal$<>""
					cRetVal$=cRetVal$+delim$
				EndIf 
				
				For char=0 To BankSize(keybank)-1
					If (Not(PeekByte(keybank,char))) 
ExitLoop%=True
Exit
					cRetVal$=cRetVal$+Chr(PeekByte(keybank,char))
				Next
			Else
				Exit
			EndIf
			
			nIdx=nIdx+1
		Wend
		reg_closekey(hKey)
	EndIf

	FreeBank keybank
	Return cRetVal$
End Function

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