vb.net - Extracting the "for" attribute from a label element in an html webpage -

i have code analyses various attributes of webpage when parts of webpage clicked. 1 of elements picked out id of clicked element.

sometimes there no id , instead element being clicked on label using "for" attribute reference id. in these case want pick "for" attribute value.

i have attempted follows:

txtid.text = trycast(myhtmldocument, htmldocument).getelementfrompoint(lastmousepos).getattribute("id") if txtid.text = ""   txtid.text = trycast(myhtmldocument, htmldocument).getelementfrompoint(lastmousepos).getattribute("for") end if 

for reason .getattribute("for") returns blank. referencing attribute wrongly - or else going on.

html example below:

<div class="question legal-owner active">  <a class="help-trigger help-trigger-layout">     <span class="help-text-icon"></span> </a>   <div class="quote-help quote-help-layout">     <a class="quote-help-close-container">         <div class="quote-help-close"></div>     </a>     <h3>car ownership</h3>      <p>         need know whether car belongs you. if don’t own car you’re registered keeper, should answer ‘no’          (the owner of car , registered keeper can different people).     </p>  </div>  <span class="editor-label question-layout">     <label for="owningandusingcarpanel_legalowner">are (or be) legal owner of car?</label> </span>      <ul class="question-layout yesno-radio-list">         <li>             <input name="owningandusingcarpanel.legalowner" id="owningandusingcarpanel_legalowner_true" type="radio" value="true">             <label for="owningandusingcarpanel_legalowner_true">                 <span>yes</span>             </label>         </li>         <li>             <input name="owningandusingcarpanel.legalowner" id="owningandusingcarpanel_legalowner_false" type="radio" value="false">             <label for="owningandusingcarpanel_legalowner_false">                 <span>no</span>             </label>         </li>     </ul> <span class="editor-validation">     <span class="field-validation-valid" id="owningandusingcarpanel_legalowner_validationmessage"></span> </span> </div> 

i have resolved creating own function called getunknown search attribute within tag. should work attribute value surrounded double quotes. function has 2 arguments, first string should contain element tag complete attributes , values, , second attribute want extract value for.

private function getunknown(mytext string, myattr string)     dim myresult string = ""     dim mystart integer = 0     dim mylen integer = 0     'remove spaces around "=" sign     dim mycleantext string = regex.replace(mytext, "\s+([=])\s+|\s+([=])|([=])\s+", "=")     'add =" attribute avoid finding non-attributes when using indexof function     dim myfullattr string = myattr.trim().tolower + "="""      try         mystart = mycleantext.tolower().indexof(myfullattr)         if mystart = -1             myresult = "nothing found"         else             mystart = mystart + myfullattr.length             mylen = mycleantext.indexof("""", mystart) - mystart             myresult = mycleantext.substring(mystart, mylen)         end if     catch ex exception         myresult = "nothing found"     end try      return myresult  end function 

in context of original question have used follows

dim myelement string = _  trycast(myhtmldocument, htmldocument).getelementfrompoint(lastmousepos).outerhtml.tostring  txtid.text = getunknown(myelement, "for")