Object Item not exists, how to catch error?

[Trolleule]

Hi,

when i try to access an object item, i get an error, but don't know how to catch this error:

 

Func GetFirewallRule($sName)
    Local $oPolicy = ObjCreate("HNetCfg.FwPolicy2")

    MsgBox(0, "test", $oPolicy.Rules.Item($sName)) ; throws error: The requested action with this object has failed.

EndFunc

Thanks in advance

Edited February 18, 2016 by Trolleule

[JLogan3o13]

Func GetFirewallRule($sName)
    Local $oPolicy = ObjCreate("HNetCfg.FwPolicy2")
       If IsObj($oPolicy) Then
          MsgBox(0, "test", $oPolicy.Rules.Item($sName)) ; throws error: The requested action with this object has failed.
       Else
          ;Do Something Else
       EndIf
EndFunc

Hi, @Trolleule Look at IsObj in the help file.

Edited February 17, 2016 by JLogan3o13

[Trolleule]

Thanks...but it's not as easy as you think  

The problem, is that 

$oPolicy.Rules ; is always ok, but
$oPolicy.Rules.Item("Test") ; will throw error, if rule with name "Test" not exists

I already tried:

$oPolicy.Rules.Exists("Test")

but this property is not known in this context

Any ideas?

 

Edited February 17, 2016 by Trolleule

[mLipok]

When you are using .....Item()

then you sould use ItemIndex instead name.

$oPolicy.Rules.Item(1))

 

Or other way like this:

GetFirewallRule('TeamViewer')

Func GetFirewallRule($sName)
    ; Error monitoring. This will trap all COM errors while alive.
    ; This particular object is declared as local, meaning after the function returns it will not exist.
    Local $oErrorHandler = ObjEvent("AutoIt.Error", "_ErrFunc")

    Local $oPolicy = ObjCreate("HNetCfg.FwPolicy2")

    Local $oRules_coll = $oPolicy.Rules
    If @error Then Return SetError(@error, @extended, '')

    For $oRule_enum In $oRules_coll
        If StringInStr($oRule_enum.name, $sName ) Then
        ConsoleWrite( $oRule_enum.name & @CRLF)
        EndIf
    Next

EndFunc    ;==>GetFirewallRule

; User's COM error function. Will be called if COM error occurs
Func _ErrFunc($oError)
    ; Do anything here.
    ConsoleWrite(@ScriptName & " (" & $oError.scriptline & ") : ==> COM Error intercepted !" & @CRLF & _
            @TAB & "err.number is: " & @TAB & @TAB & "0x" & Hex($oError.number) & @CRLF & _
            @TAB & "err.windescription:" & @TAB & $oError.windescription & @CRLF & _
            @TAB & "err.description is: " & @TAB & $oError.description & @CRLF & _
            @TAB & "err.source is: " & @TAB & @TAB & $oError.source & @CRLF & _
            @TAB & "err.helpfile is: " & @TAB & $oError.helpfile & @CRLF & _
            @TAB & "err.helpcontext is: " & @TAB & $oError.helpcontext & @CRLF & _
            @TAB & "err.lastdllerror is: " & @TAB & $oError.lastdllerror & @CRLF & _
            @TAB & "err.scriptline is: " & @TAB & $oError.scriptline & @CRLF & _
            @TAB & "err.retcode is: " & @TAB & "0x" & Hex($oError.retcode) & @CRLF & @CRLF)
EndFunc    ;==>_ErrFunc

 

Some reference:

https://msdn.microsoft.com/en-us/library/windows/desktop/aa365322(v=vs.85).aspx
https://msdn.microsoft.com/en-us/library/windows/desktop/aa364724(v=vs.85).aspx

[Trolleule]

yeah thats the solution i'm currently using, but only a workaround...i think.

thanks for your time mLipok!  

Quote

When you are using .....Item()

then you sould use ItemIndex instead name

see https://msdn.microsoft.com/en-us/library/aa365348(v=vs.85).aspx

Func FirewallRuleExists($sName)
    Local $oPolicy = ObjCreate("HNetCfg.FwPolicy2")
    Return (IsObj($oPolicy.Rules.Item($sName))) ? 1 : 0
EndFunc

The one liner is smarter, but i think it's not possible to catch this error with autoit, what do you mean?

Is there something to prevent autoit from crashing in this case?

 

EDIT:

ok i can catch it with  Global $oErrorHandler = ObjEvent("AutoIt.Error", "_ErrFunc")

but then every error will be catched. Is it possible to catch only error from the policy object and normal errors like syntax and so on will cause a crash?

Edited February 17, 2016 by Trolleule

[Trolleule]

I did it like

expandcollapse popup

Func FirewallRuleExists($sName)
    Local $oPolicy = ObjCreate("HNetCfg.FwPolicy2")
    Return (IsObj($oPolicy.Rules.Item($sName))) ? 1 : 0
EndFunc


Func Template_COMErrorRegister()
    $__g_oTemplateCOMErrorHandler = ObjEvent("AutoIt.Error", "Template_COMErrFunc")
EndFunc   ;==>Template_COMErrorRegister


Func Template_COMErrorUnregister()
    $__g_oTemplateCOMErrorHandler = 0
EndFunc   ;==>Template_COMErrorUnregister


Func Template_COMErrFunc()
    ; Do nothing special, just check @error after suspect functions.
EndFunc   ;==>Template_COMErrFunc

Func GetOutgoingTrafficRules()
    
    Template_COMErrorRegister()
    Local $aCurExplorerOptions[] = [ _
        FirewallRuleExists('"AADBrokerPlugin"-App') , _
        FirewallRuleExists('"AppAccountsControl"-App') , _
        FirewallRuleExists('"BioEnrollment"-App') , _
        FirewallRuleExists('"LockApp"') , _
        FirewallRuleExists('"Edge"-App (Teil 1/2)') , _
        FirewallRuleExists('"Edge"-App (Teil 2/2)') , _
        FirewallRuleExists('"AssignedAccessLockApp"-App') , _
        FirewallRuleExists('"Background Task Host"-Prozesses') , _
        FirewallRuleExists('"Download Upload Host"-Prozesses') , _
        FirewallRuleExists('"Hostprozesses für Windows-Aufgaben"') , _
        FirewallRuleExists('"Host Process for Setting Synchronization"') , _
        FirewallRuleExists('"Microsoft Compatibility Telemetry"-Prozesses') , _
        FirewallRuleExists('"FeedbackSIUFDeployment"-Prozesses') , _
        FirewallRuleExists('"Feeds Synchronization"-Prozesses') , _
        FirewallRuleExists('"MalwareProtectionCommandLineUtility"-Prozesses') , _
        FirewallRuleExists('"Windows-Tools zum Entfernen bösartiger Software"') , _
        FirewallRuleExists('"RuntimeBroker"-Prozesses') , _
        FirewallRuleExists('"SIH Client"-Prozesses') , _
        FirewallRuleExists('"Problem Reporting"-Prozesses') , _
        FirewallRuleExists('"SQM-Konsolidator"-Prozesses') , _
        FirewallRuleExists('"Windows-Aktivierungsclient"-Prozesses') , _
        FirewallRuleExists('"Device Association Framework Provider Host"-Prozesses') _
    ]
    Template_COMErrorUnregister()
    
    Return $aCurExplorerOptions
EndFunc

Not much better, but so i don't need to do an arraysearch for every rule

[mLipok]

2 hours ago, Trolleule said:

see https://msdn.microsoft.com/en-us/library/aa365348(v=vs.85).aspx

Func FirewallRuleExists($sName)
    Local $oPolicy = ObjCreate("HNetCfg.FwPolicy2")
    Return (IsObj($oPolicy.Rules.Item($sName))) ? 1 : 0
EndFunc

 

"HNetCfg.FwPolicy2" is not the same as:
https://msdn.microsoft.com/en-us/library/aa365348(v=vs.85).aspx

"HNetCfg.FwPolicy2" is described here:
https://msdn.microsoft.com/en-us/library/windows/desktop/aa365322(v=vs.85).aspx

 

[Trolleule]

yes but  "HNetCfg.FwPolicy2"  is/was not the problem...

[mLipok]

So what is the problem ?

[Trolleule]

oh you are right. So it have to be look like

Func FirewallRuleExists($sName)
    Local $oRules = ObjCreate("HNetCfg.FwRules")
    MsgBox(0, $oRules, VarGetType($oRulesy)) ; $oRules is 0 
    Return (IsObj($oRules.Item("Test"))) ? 1 : 0
EndFunc

but the object returns always 0. Do you know why?

[Danyfirex]

Why not simply Return IsObj($oRules.Item("Test")) instead Return (IsObj($oRules.Item("Test"))) ? 1 : 0

 

Saludos

[Trolleule]

shit thats right too @Danyfirex

i edited the code too much times, didn't see that

Strangely the object "HNetCfg.FwRules" can't be accessed. When i google for 

Quote

"HNetCfg.FwRules"

the results are always

Quote

"HNetCfg.FwRule"

which is not the same, but the documentation says this is a valid interface...no special remarks or something :S

[Trolleule]

@mLipok now i got it -> it's the same, because

Quote

INetFwPolicy2.Rules( _
  ByRef rules, _
  ByRef rules _
) As INetFwRules

it returns a INetFwRules object...i know this shit is confusing :/

this explains why i can't access  "HNetCfg.FwRules" in this manner...