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Website Forms with Viewstate and Eventvalidation

 Keywords:  Form .NET Viewstate Eventvalidation _Viewstate _Eventvalidation click fireevent No Navigate

Question:

We have an internal Website which includes a HTML login page. Using iContentUrl to populate the HTML Form data on the Login page I can successfully POST the form data to the Site and login.

This website has been updated to .NET and now this process does not work and the Website acts like it never received the POST.

The only difference I can see between the Forms are that .NET web pages include hidden fields __VIEWSTATE, __EVENTVALIDATION, __EVENTARGUMENT & __EVENTTARGET.

Fields __VIEWSTATE and __EVENTVALIDATION have values embedded in the HTML Form. So I first read the HTML Form into a File and read this files to extract the Values for these Fields and then include them in the form POST but the Website does nothing with the POST which implies the POST is being dropped as invalid.

The Login page works when manually accessed by IE or FireFox but I have not tried using the IE Object as I already had a working extender version so was hoping this method would still work. The Page designer added nothing to the Page creation these new hidden fields where added by the .NET development tool and his code does not explicitly check these POST values yet the other POST Value check code is never being called then a POST is sent from the Extender.

There is no JSESSIONID reference in the HTML and the designer did not request JSON but again this may be something the .NET development tools has added?

Answer:

__VIEWSTATE and __EVENTVALIDATION are encrypted data blocks which are used as a sort of protected storage for persisting state in ASP.NET sessions. I believe that your POST message must return them, exactly as you receive them. Their absence probably causes the ASP.NET runtime engine to discard the response.

Try modifying your code to use the IE object instead. I believe this des support and work with the __Viewstate __Eventvalidation fields.

;***************************************************************************
;**                  EODDATA Auto-Login and download
;**      Logs into your EODDATA account online and attempts to download data.
;**
;**       Ensure that you are signed-out of EODDATA before running!
;**       Avoid use of Navigate method or __viewstate is lost!
;**       Method used for Click can change based on IE versions/Settings?
;**
;** Developer: Deana Falk 2014.04.11
;***************************************************************************

;!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
; Ensure that you are signed-out of EODDATA before running
;!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

#DefineFunction udfIEPageLoadWait( objIE )
    ; Wait for webpage to load
    While !(objIE.readyState == 'complete' || objIE.readyState == 4 )
       TimeDelay(0.1)
    EndWhile
    While !(objIE.document.readyState == 'complete' || objIE.document.readyState == 4 )
       TimeDelay(0.1)
    EndWhile
    Return 1
#EndFunction

#DefineFunction udfClick(oIE, oElement)
   ; Used Click button on IE 9 and newer
   oEvent = oIE.Document.createEvent("HTMLEvents")
   If oEvent
      oEvent.initEvent("click", @TRUE, @TRUE)
      oElement.dispatchEvent(oEvent)
   Else
      oElement.fireEvent("onclick")
   EndIf
#EndFunction

url = 'http://www.eoddata.com'

EODData_Login =  "soandso@blahblah.com" ; MODIFY TO FIT YOUR NEEDS
EODData_Password = "****" ; MODIFY TO FIT YOUR NEEDS

oIE = ObjectCreate('internetexplorer.application')
oIE.visible = @true;
oIE.navigate(url);

udfIEPageLoadWait( oIE )

; Wait for First element ( helps with timing )
While @TRUE
   oElement = oIE.Document.getElementById("ctl00_cph1_lg1_txtEmail")
   type = ObjectTypeGet(oElement)
   If type != 'NULL' Then Break
EndWhile
oElement.value = EODData_Login

oElement = oIE.Document.getElementById("ctl00_cph1_lg1_txtPassword")
oElement.value = EODData_Password

; Click button
oElement = oIE.Document.getElementById("ctl00_cph1_lg1_btnLogin")
;oElement.Click
;or
; Click button on IE 9 and newer
; createEvent initEvent DispatchEvent
;oEvent = oIE.Document.createEvent("HTMLEvents")
;oEvent.initEvent("click", @TRUE, @TRUE)
;oElement.dispatchEvent(oEvent)
udfClick(oIE, oElement)
oEvent = 0
oElement = 0

udfIEPageLoadWait( oIE )

; Click link to go to download section
; Use Click link method in stead of Navigate() because Navigates losses __ViewState logginn info
LinksCollection = oIE.document.links
ForEach link In LinksCollection
   Link_Href = StrTrim(link.href)
   Link_Exist =  StrIndexNC(Link_Href, "download.aspx", 1, @FWDSCAN);!!!!!!!
   If Link_Exist == 0 Then Continue
   ; Click link
   udfClick(oIE, link)
Next

udfIEPageLoadWait( oIE )

; Select Downlad Details
While @TRUE
   oElement = oIE.document.getElementsByTagName("select")
   type = ObjectTypeGet(oElement)
   If type != 'NULL' Then Break
   TimeDelay(0.25)
EndWhile
oExchange = oElement.Item(0) ; select the exchange
Select_ExchangePos = 20 ; Nasdaq
oExchange.Options.Item(Select_ExchangePos).selected = @TRUE ; set the exchange
oFormat= oIE.document.getElementsByTagName("select").item(1) ; Set the format
Select_FormatPos = 1
oFormat.Options.item(Select_FormatPos).selected = @TRUE
oIE.document.GetElementByid("ctl00_cph1_d1_chkAllSymbols").checked = 1
oIE.document.GetElementByid("ctl00_cph1_d1_chkAllSymbols").fireevent("onclick")

; Wait for Download button element element
While @TRUE
   oElement = oIE.Document.getElementById("ctl00_cph1_d1_btnDownload")
   type = ObjectTypeGet(oElement)
   If type != 'NULL' Then Break
EndWhile
; Click Download button element element
udfClick(oIE, oElement)

TimeDelay(3)

SendKey( '{TAB 2}' )
SendKey( '{DOWN 2}' )
SendKey( '{ENTER}' )

oEvent = 0
oElement = 0
oSelect_Format = 0
oExchange = 0
oIE = 0
Exit

Article ID:   W17624
Filename:   Website Forms with Viewstate and Eventvalidation .txt
File Created: 2017:07:28:12:58:49
Last Updated: 2014:04:11:09:57:51