How to judge that the object is no longer existing or unusable?

[Letraindusoir]

#include <IE.au3>

Local $oIE = _IECreate("http://www.autoitscript.com")

For $i = 0 To 20
    ConsoleWrite("isObj($oIE) = " & isObj($oIE) & @CRLF)
Next

Do
  ProcessClose("iexplore.exe")
  Sleep(100)
Until (Not ProcessExists("iexplore.exe"))

Sleep(2000)
ConsoleWrite(@CRLF & "ProcessCloseed...." & @CRLF & @CRLF)

For $i = 0 To 20
    ConsoleWrite("isObj($oIE) = " & isObj($oIE) & @CRLF)
Next

MsgBox(4096,"url",$oIE.document.parentWindow.location.href)

As in the above example, when open the IE browser,  the object variable $oIE is obtained.

But when the browser is shut down, the $oIE  still exists as  the object variable.

This causes unpredictable errors during the script running and even causes the script to crash.

Using ObjEvent("AutoIt.Error")  capture errors but can cause the script to crash sometime.

Are there any other ways to detect absent or unavailable object variables?

thanks!

[Nine]

23 minutes ago, Letraindusoir said:

Using ObjEvent("AutoIt.Error")  capture errors but can cause the script to crash sometime.

I would like to see a script that causes AutoIt to crash because of the use of ObjEvent.  I am using it all the time, and never seen a crash caused by it.  Really would love to see a replicable script...

[water]

This works for me: 

#include <IE.au3>

Global $oIE = _IECreate("http://www.autoitscript.com")
Global $oErrorHandler = ObjEvent("AutoIt.Error", "_ErrorFunc")
For $i = 0 To 20
    ConsoleWrite("isObj($oIE) = " & IsObj($oIE) & @CRLF)
Next
Do
    ProcessClose("iexplore.exe")
    Sleep(100)
Until (Not ProcessExists("iexplore.exe"))
Sleep(2000)
ConsoleWrite(@CRLF & "ProcessClosed...." & @CRLF & @CRLF)
For $i = 0 To 20
    ConsoleWrite("isObj($oIE) = " & IsObj($oIE) & @CRLF)
Next
Global $sURL = $oIE.document.parentWindow.location.href ; COM Error handler does not return the error raised by document but by href. Does value does not explain the real problem!
if @error = 0x800706BA Then Exit MsgBox(0, "Error #1", "RPC-Server is no longer available - means: IE has been closed by user!")
Global $oDocument = $oIE.document
if @error = 0x800706BA Then Exit MsgBox(0, "Error #2", "RPC-Server is no longer available - means: IE has been closed by user!")

Func _ErrorFunc($oError)
    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

You will notice that you only get message "Error #2". But you get 2 COM errors written to the console with the same error code.
The problem is caused by AutoIt having problems with nested COM operations where more than 1 operation fails. This could cause the crashes you encounter!

[Nine]

@waterOn Win7, I get to have error #1 but the error number returned by @error is 1 (I removed the exit).  Only second error returns 0x800706BA.

Edited February 12, 2022 by Nine

[water]

The only solution to this problem is to avoid nesting:

#include <IE.au3>

Global $oIE = _IECreate("http://www.autoitscript.com")
Global $oErrorHandler = ObjEvent("AutoIt.Error", "_ErrorFunc")
For $i = 0 To 20
    ConsoleWrite("isObj($oIE) = " & IsObj($oIE) & @CRLF)
Next
Do
    ProcessClose("iexplore.exe")
    Sleep(100)
Until (Not ProcessExists("iexplore.exe"))
Sleep(2000)
ConsoleWrite(@CRLF & "ProcessClosed...." & @CRLF & @CRLF)
For $i = 0 To 20
    ConsoleWrite("isObj($oIE) = " & IsObj($oIE) & @CRLF)
Next
; Global $sURL = $oIE.document.parentWindow.location.href ; COM Error handler does not return the error raised by document but by href. Does value does not explain the real problem!
Global $oDocument = $oIE.document
if @error = 0x800706BA Then Exit MsgBox(0, "Error #1", "RPC-Server is no longer available - means: IE has been closed by user!")
Global $sURL = $oDocument.parentWindow.location.href

Func _ErrorFunc($oError)
    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

As IE is no longer available, we know that the error occurs after the first operation.
If the first operation is successful we can then use nested oprations.

[ad777]

@Letraindusoir

object is no longer existing or unusable?

Do
    ; ProcessClose("iexplore.exe")
    Sleep(100)
Until (Not ProcessExists("iexplore.exe"))
Sleep(2000)
ConsoleWrite(@CRLF & "Obj is Unusable" & @CRLF & @CRLF)
For $i = 0 To 20
    ;ConsoleWrite("isObj($oIE) = " & IsObj($oIE) & @CRLF)
Next

 

[water]

I think you misunderstood the OPs problem.
When IE is closed while the script is still running it will crash the next time it tries to access the IE object.
 

[mLipok]

 

4 hours ago, Letraindusoir said:

Using ObjEvent("AutoIt.Error")  capture errors but can cause the script to crash sometime.

it was fixed:

https://www.autoitscript.com/trac/autoit/ticket/3167

and is in recent beta:

There is workaround, you should split this:

$oIE.document.parentWindow.location.href

  into:

Local $oCOMErrorHandler = ObjEvent("AutoIt.Error") 
 
Local $oDocument = $oIE.document
if @error .....

Local $oWindow = $oDocument.parentWindow
if @error .....

Local $oLocation = $oWindow.location
if @error .....

Local $sHREF = $oLocation.href
if @error .....

 

Edited February 12, 2022 by mLipok

[water]

9 hours ago, mLipok said:

There is workaround, you should split this:

$oIE.document.parentWindow.location.href

  into:

Local $oCOMErrorHandler = ObjEvent("AutoIt.Error") 
 
Local $oDocument = $oIE.document
if @error .....

Local $oWindow = $oDocument.parentWindow
if @error .....

Local $oLocation = $oWindow.location
if @error .....

Local $sHREF = $oLocation.href
if @error .....

Exactly what I posted here

 

[Gianni]

ok what @water said, is the right way. ...also, and just for the record... if you don't want to use something like ObjEvent ("AutoIt.Error", ...) there is also another "quick and dirty" workaround to avoid crashes that I've seen used by @genius257 here: https://www.autoitscript.com/forum/topic/185387-value-of-js-variable-in-ie/?do=findComment&comment=1332372 and explained here: https://www.autoitscript.com/forum/topic/185387-value-of-js-variable-in-ie/?do=findComment&comment=1332585

in short you could wrap your "$oIE.document.parentWindow.location.href" (or whatever) in an Execute() statement and check for errors right after the call, that way you can see if something went wrong without a "crash", something like this:

$vResult = Execute('$oIE.document.parentWindow.location.href')
If @error Then Exit MsgBox(0, 'sorry', '...something went wrong.')

 

[water]

Means: Stop automating IE, move to Chrome, Edge or Firefox and use the WebDriver UDF to automate this browsers

[Gianni]

34 minutes ago, water said:

... Means: Stop automating IE, move to Chrome, Edge or Firefox and use the WebDriver UDF to automate this browsers

I agree, however IE can still be very useful in terms of being "embedded" in the GUIs, which is not so simple (so far) for other browsers

[Letraindusoir]

Thank every master for advice!

Capturing the error with 'ObjEvent' seems to be not accurate enough and I have used it for the debugging stage before.

Capture error reprocessing (try....Catch.....) ,I don't know how to use it, so often causing the script to be interrupted or not robust enough.

expandcollapse popup

#include <IE.au3>

Global $oErrorHandler = ObjEvent("AutoIt.Error", "_ErrorFunc")
Global $oDocument = 0
Global $oIE = 0, $sURL = ""

$oIE = _IECreate("https://www.autoitscript.com/site/", 1,1,1,1)
If Not IsObj($oIE) Then Exit

Local $oSlider = 0
Local $bClicked = False
Local $n = 0
While 1
    If $n > 50 Then ExitLoop
    If Not IsObj($oIE) Then $oIE = _IECreate("https://www.autoitscript.com/site/", 1,1,1,1)
    $oDocument = $oIE.document
    If @error = 0x800706BA Then Exit MsgBox(0, "Error #1", "RPC-Server is no longer available - means: IE has been closed by user!")
    $sURL = $oDocument.parentWindow.location.href
    ConsoleWrite("src = " & $sURL & @CRLF)
    
    If ($bClicked = False) Then
        _IENavigate($oIE, "https://www.autoitscript.com/forum/")
        $oSlider = _IEGetObjById($oIE, "ukpt_slider")
        If IsObj($oSlider) Then
            $oSlider.click()
            $bClicked = True
        EndIf
    EndIf
    $n += 1
WEnd

Func _ErrorFunc($oError)
    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   ;==>_ErrorFunc

If Not  IsObj($oIE) Then $oIE = _IECreate("https://www.autoitscript.com/site/", 1,1,1,1)

if find that the "$oIE"  object is no longer existing or unusable(For either unforeseen or unknown reasons), then _IECreate it again...

Edited February 14, 2022 by Letraindusoir