I am attempting to run this JS function when a user clicks on a Panel (in a TableCell). This Panel is an element in a Content Page, which is used with the Master Page which has a Content Place Holder. When I try to click on the panel, the following error is thrown:

Microsoft JScript runtime error: Object doesn't support this property or method

Here is the relevant code for the Master page ASPX:

       <link rel=Stylesheet href=../includes/styles.css />

       <script type=text/javascript language=javascript>

           function swapDirections(control) {

               var main = document.getElementByID('ct100_TableContent_' + control);

               var long = document.getElementById('ct100_TableContent_' + control + '_long');

               var short = document.getElementById('ct100_TableContent_' + control + '_short');



               var mainhtml = main.innerHTML;

               var longhtml = long.innerHTML;

               var shorthtml = short.innerHTML;



               if (mainhtml.length == shorthtml.length)

                   main.innerHTML = longhtml;

               else

                   main.innerHTML = shorthtml;

           }

        </script>

Here is the relevant code for the Content page:

            Panel rigDirections = new Panel();

            rigDirections.CssClass = clip;

            rigDirections.ID = u.Id.ToString() + _RD;

            string MainDivRD = rigDirections.ClientID;

            Literal rigDir = new Literal();

            string sshort = ;

            if (u.RigDirections.ToLower().Length > (textCutOFF + 4))

            {

                sshort = Server.HtmlEncode(u.RigDirections.ToLower().Substring(0, textCutOFF).Trim()) +  ...;

                rigDir.Text = <a class=RD_RA title=Click to Expand href=javascript: swapDirections(' + MainDivRD + ')> + sshort + </a>; ;

            }

            else

            {

                sshort = Server.HtmlEncode(u.RigDirections.ToLower().Trim());

                rigDir.Text = sshort ;

            }

            string slong = Server.HtmlEncode(u.RigDirections.ToLower().Trim());



            rigDirections.Controls.Add(rigDir);

            cell.Controls.Add(rigDirections);    

And the Content Page ASPX:

      <asp:Content ID=Content1 ContentPlaceHolderID=TableContent Runat=Server>



       <asp:Panel ID=pnlTable Width=950 runat=server>



       </asp:Panel>

      </asp:Content>

The error is being thrown on the first line of the function.

I have exhausted my internet searching skills, and I have never used JS before, so if anyone has any ideas I would greatly appreciate them.

Thanks!

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