counting id attributes

[solomon]

Hi

Javascript newbie here - I know my way around a bit of serverside and SQL stuff but client side still eludes me slightly.

On a page, I have several div tags with incrementally numbered id attributes:

<div id="content[1]">blah blah</div>
<div id="content[2]">yada yada</div>
<div id="content[3]">rhubarb rhubarb</div>

What I need is a function that can count the number of 'content' div tags - i.e. how large the content array is.

I've taken a pre-written script and jigged with it so it does what I need but currently I need to manually update a variable holding how many content div tags there are which is an ugly solution.

Can anyone help me out please? Thanks in advance!

P.S. This is my script as it currently stands. Any advice is welcomed :

function DS_switchto(id)
    {
    var numberofpages=2;
    if (document.all)
        {
        for (z = 1; z <= numberofpages; z++)
            {
            document.all['content['+z+']'].style.display = 'none';
            }
        document.all['content['+id+']'].style.display = '';
        return false;
        } else if (document.getElementById)
        {
        for (z = 1; z <= numberofpages; z++)
            {
            document.getElementById['content['+z+']'].style.display = 'none';
            }
        document.getElementById('content['+id+']').style.display = 'block';
        return false;
        }
    }

[AdamGundry]

Perhaps something like this...

function switch2(id){
  divs = document.getElementsByTagName('div');
  for (var i=0; i<divs.length; i++)
    if (divs[i].id.substr(0, 7) == 'content')
      divs[i].style.display = (divs[i].id.substr(8, 1) == id ? 'block' : 'none');
}

Adam

[solomon]

Excellent! that works a treat - thanks Adam.

I was only expecting a system to count the div tags, but you clearly can't bear to see clumsy scripting