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html - Is there a way in VBA to get elements produced by javascript?

I've been doing Google detective work for a few hours (including searching StackOverflow) for a technique to allow targeting of HTML elements produced by JavaScript in VBA.

As an example, I cannot use ie.Document.getElementById(id) on this: http://www.kisfutures.com/electronic.html?page=quote&sym=NGU12&mode=i

However, that method is quite capable of finding elements on static pages, as tested on google.com.

I've played with simply getting all the InnerText from Document.body and then parsing the file for my desired TD values, but I ran into a roadblock when trying to split two values that are on different lines. As an illustration, the following was understood by Split(..) as "2040":

20
40

From what I understand, the problem with getElementById(id) is that the website's table is generated by JavaScript after the page has loaded, and thus any elements created by that JavaScript cannot be targeted by my VBA code. Is there anyway to have my VBA code see this JavaScript-generated content?

Thank you for your help!

Edit

The VBA code being used:

Function Quote(Market, Parameter)
    Set ie = CreateObject("InternetExplorer.Application")
    ie.Navigate "http://www.kisfutures.com/electronic.html?page=quote&sym=NGU12&mode=i"
    While ie.Busy
        DoEvents
    Wend
    Dim id As String
    id = "dt1_" & Market & "_" & StrConv(Parameter, vbLowerCase)
    Quote = ie.Document.getElementByID(id).InnerText
    ie.Quit
End Function

Basically I try to build an HTML element ID using the column header for the Market. So if, for example the market is "NGU12" and the column header is "Open", the ID built is: "dt1_NGU12_open", which is the ID for the TD element containing the "Open" value for market NGU12.

See Question&Answers more detail:os

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1 Answer

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As Tim has mentioned there should be no difference between statically and dynamically generated content when attempting access. Try this:

Function Quote(Market, Parameter)
    Set ie = CreateObject("InternetExplorer.Application")
    ie.Navigate "http://www.kisfutures.com/electronic.html?page=quote&sym=NGU12&mode=i"
    While ie.Busy
        DoEvents
    Wend
    Application.Wait Now + TimeSerial(0,0,1) 'Pause 1 second, hopefully
                                             'the dynamic content is 
                                             'generated within this 
                                             'time-frame
    Dim id As String
    id = "dt1_" & Market & "_" & StrConv(Parameter, vbLowerCase)
    Quote = ie.Document.getElementByID(id).InnerText
    ie.Quit
End Function 

There are better ways of halting execution (see Windows Sleep API) but I'll leave that to you if you need more fine-grained control.

Also, if you'd like to test whether a specific id exists after the page has been generated you could load the page manually in IE and add a bookmarklet containing the following as the URL:

javascript:void((function() {var a = document.getElementById(prompt('Please enter an id to test','dt1_NGU12_open')); if (a) {alert('Element found');} else {alert('Element not found')};})())

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