Use getElementById on HTMLElement instead of HTMLDocument

Question

I ve been playing around with scraping data from web pages using VBS VBA   If it were Javascript I d be away as its easy  but it doesn t seem to be quite as straight forward in VBS VBA   This is an example I made for an answer  it works but I had planned on accessing the child nodes using getElementByTagName but I could not figure out how to use them  The HTMLElement object does not have those methods   Sub Scrape   Dim Browser As InternetExplorer Dim Document As HTMLDocument Dim Elements As IHTMLElementCollection Dim Element As IHTMLElement  Set Browser   New InternetExplorer  Browser navigate  http   www hsbc com about-hsbc leadership   Do While Browser Busy And Not Browser readyState   READYSTATE COMPLETE     DoEvents Loop  Set Document   Browser Document  Set Elements   Document getElementsByClassName  profile-col1    For Each Element in Elements     Debug Print     name     amp  Trim Element Children 1  Children 0  innerText      Debug Print    title     amp  Trim Element Children 1  Children 1  innerText  Next Element  Set Document   Nothing Set Browser   Nothing End Sub   I have been looking at the HTMLElement document property  seeing if it is like a fragment of the document but its either difficult to work with or just isnt what I think  Dim Fragment As HTMLDocument Set Element   Document getElementById  example     This works Set Fragment   Element document   This doesn t   This also seems a long winded way to do it  although thats usually the way for vba imo    Anyone know if there is a simpler way to chain functions   Document getElementById  target   getElementsByTagName  tr   would be awesome

User · Answer

Sub Scrape       Dim Browser As InternetExplorer     Dim Document As htmlDocument     Dim Elements As IHTMLElementCollection     Dim Element As IHTMLElement      Set Browser   New InternetExplorer     Browser Visible   True     Browser navigate  http   www stackoverflow com       Do While Browser Busy And Not Browser readyState   READYSTATE COMPLETE         DoEvents     Loop      Set Document   Browser Document      Set Elements   Document getElementById  hmenus   getElementsByTagName  li       For Each Element In Elements         Debug Print Element innerText          Questions          Tags          Users          Badges          Unanswered          Ask Question     Next Element      Set Document   Nothing     Set Browser   Nothing End Sub

User · Answer

I would use XMLHTTP request to retrieve page content as much faster  Then it is easy enough to use querySelectorAll to apply a CSS class selector to grab by class name  Then you access the child elements by tag name and index   Option Explicit Public Sub GetInfo       Dim sResponse As String  html As HTMLDocument  elements As Object  i As Long      With CreateObject  MSXML2 XMLHTTP            Open  GET    https   www hsbc com about-hsbc leadership   False          setRequestHeader  If-Modified-Since    Sat  1 Jan 2000 00 00 00 GMT           send         sResponse   StrConv  responseBody  vbUnicode      End With     Set html   New HTMLDocument     With html          body innerHTML   sResponse         Set elements    querySelectorAll   profile-col1           For i   0 To elements Length - 1             Debug Print String 20  Chr  61               Debug Print elements item i  getElementsByTagName  a   0  innerText             Debug Print elements item i  getElementsByTagName  p   0  innerText             Debug Print elements item i  getElementsByTagName  p   1  innerText         Next     End With End Sub     References   VBE   Tools   References   Microsoft HTML Object Library

User · Answer

I don t like it either   So use javascript   Public Function GetJavaScriptResult doc as HTMLDocument  jsString As String  As String      Dim el As IHTMLElement     Dim nd As HTMLDOMTextNode      Set el   doc createElement  INPUT       Do         el ID   GenerateRandomAlphaString 100      Loop Until Document getElementById el ID  Is Nothing     el Style display    none      Set nd   Document appendChild el       doc parentWindow ExecScript  document getElementById     amp  el ID  amp      value      amp  jsString      GetJavaScriptResult   Document getElementById el ID  Value      Document removeChild nd  End Function   Function GenerateRandomAlphaString Length As Long  As String      Dim i As Long     Dim Result As String      Randomize Timer      For i   1 To Length         Result   Result  amp  Chr Int Rnd Timer    26   65   Round Rnd Timer     32       Next i      GenerateRandomAlphaString   Result  End Function   Let me know if you have any problems with this  I ve changed the context from a method to a function   By the way  what version of IE are you using  I suspect you re on  lt  IE8  If you upgrade to IE8 I presume it ll update shdocvw dll to ieframe dll and you will be able to use document querySelector All   Edit  Comment response which isn t really a comment  Basically the way to do this in VBA is to traverse the child nodes  The problem is you don t get the correct return types  You could fix this by making your own classes that  separately  implement IHTMLElement and IHTMLElementCollection  but that s WAY too much of a pain for me to do it without getting paid     If you re determined  go and read up on the Implements keyword for VB6 VBA   Public Function getSubElementsByTagName el As IHTMLElement  tagname As String  As Collection      Dim descendants As New Collection     Dim results As New Collection     Dim i As Long      getDescendants el  descendants      For i   1 To descendants Count         If descendants i  tagname   tagname Then             results Add descendants i          End If     Next i      getSubElementsByTagName   results  End Function  Public Function getDescendants nd As IHTMLElement  ByRef descendants As Collection      Dim i As Long     descendants Add nd     For i   1 To nd Children Length         getDescendants nd Children Item i   descendants     Next i End Function

User · Answer

Thanks to dee for the answer above with the Scrape   subroutine  The code worked perfectly as written  and I was able to then convert the code to work with the specific website I am trying to scrape   I do not have enough reputation to upvote or to comment  but I do actually have some minor improvements to add to dee s answer    You will need to add the VBA Reference via  Tools References  to  Microsoft HTML Object Library in order for the code to compile  I commented out the Browser Visible line and added the comment as follows   if you need to debug the browser page  uncomment this line   Browser Visible   True  And I added a line to close the browser before Set Browser   Nothing   Browser Quit    Thanks again dee   ETA  this works on machines with IE9  but not machines with IE8  Anyone have a fix   Found the fix myself  so came back here to post it  The ClassName function is available in IE9  For this to work in IE8  you use querySelectorAll  with a dot preceding the class name of the object you are looking for    Set repList   doc getElementsByClassName  reportList    only works in IE9  not in IE8 Set repList   doc querySelectorAll   reportList          this works in IE8

[vba] Use getElementById on HTMLElement instead of HTMLDocument

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