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ASP.NET  + javascript:  can't recognize form elements?

Posted on 2004-11-22
Medium Priority
Last Modified: 2008-02-01
I am trying to access form elements in order to hide show div tags, the hide show part is easy but I keep getting a null reference.. it doesn't see my form!

When I write out document.forms.length  the resulting value is 0!!

when i write out elem.id after it is set, it will print out the appropriate element id that I had passd in.. so why does it sometimes know the element is there but can not find my form name?


      function ShowConfiguration(id)
      var elem = self.document.getElementById(id);
        var formElements = document.frmQuery.elements; //  becomes null.
      for(var i=0; i <  formElements.length; i++) //errors here saying formElements is null
            if(formElements[i] != null && formElements[i].substring(0,3)=="mnu")
                  if(elem.id == formElements[i].id)
                        //elem.style.display = 'block';
                        //elem.style.visibility = 'visible';
                        elem.style.display ='none';      
                        elem.style.visibility ='hidden';
                        formElements[i].style.display = 'block';
                        formElements[i].style.visibility = 'visible';
                        //elem.style.display ='none';      
                        //elem.style.visibility = 'hidden';

parts of html:

            <form name="frmQuery" method="post" action="mainChart.aspx" id="frmQuery">

this form has some nested div tags who's id's will be passed by the onclick event of other buttons.

button code:
<TD><A class="menuLink" id="hypDataPullTimes" onclick="javascript:ShowConfiguration('mnuTransferTimes');"
                                                href="#">Data Pull Times</A>

Question by:bswiftly

Author Comment

ID: 12655577
well I stared at that solution for a day and decided to do a work around.. definately not a scalable piece of javascript but this is it:

And I'm not sure why I had to put this at the end outside of all the HTML, but i got different results outside the HEAD tag as to within it. I thought Head Tag code was rendered first ?  ah well.. I'll leave this question open in case anyone can substitude mnuElems.length in the following code for document.formName.elements, and then you will get points.    Remember..this is asp.net...which is I think the big problem here.. damn M$.

 function ShowConfiguration(id)
      var elem = document.getElementById(id);
      var mnuElems = ["mnuTransferTimes","mnuSingleRetId"];
      var tmpElem;
      for(var i = 0; i<mnuElems.length;i++)
            tmpElem = document.getElementById(mnuElems[i]);
            tmpElem.style.display ='none';      
            tmpElem.style.visibility ='hidden';
       elem.style.display = 'block';
       elem.style.visibility = 'visible';


Accepted Solution

modulo earned 0 total points
ID: 12889405
Closed, 50 points refunded.

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