Is there a way to set onclick to true on page load?

Basically, I am controlling a series of items through metadata, and I want to know if there is a way I can set the onClick property to "true" when the page is loaded? My issue is that I have a bunch of links that expand on click to show new links (through js) and when the user is on a specific link in that page, I want it to stay expanded, but the default is that it is collapsed on page load. I am fairly lost when it comes to js and I can't seem to figure out a way to handle it. Does this make sense? I tried doing it on the code behind of my page, but adding the server control to the div kills the script by adding "ct100_" to it's id.

My JavaScript is this:
function toggleblocks (postid) {
for (i = 1; i <= 3; i++) {
var title_id = 'title_' + i;
var title = document.getElementById(title_id);

var block = ' ...