SlickGrid has this functionality, see the tree demo.
If you want to build your own, here is an example (jsFiddle demo): Build your table with a data-depth attribute to indicate the depth of the item in the tree (the levelX CSS classes are just for styling indentation):
<table id="mytable">
<tr data-depth="0" class="collapse level0">
<td><span class="toggle collapse"></span>Item 1</td>
<td>123</td>
</tr>
<tr data-depth="1" class="collapse level1">
<td><span class="toggle"></span>Item 2</td>
<td>123</td>
</tr>
</table>
Then when a toggle link is clicked, use Javascript to hide all <tr> elements until a <tr> of equal or less depth is found (excluding those already collapsed):
$(function() {
$('#mytable').on('click', '.toggle', function () {
//Gets all <tr>'s of greater depth below element in the table
var findChildren = function (tr) {
var depth = tr.data('depth');
return tr.nextUntil($('tr').filter(function () {
return $(this).data('depth') <= depth;
}));
};
var el = $(this);
var tr = el.closest('tr'); //Get <tr> parent of toggle button
var children = findChildren(tr);
//Remove already collapsed nodes from children so that we don't
//make them visible.
//(Confused? Remove this code and close Item 2, close Item 1
//then open Item 1 again, then you will understand)
var subnodes = children.filter('.expand');
subnodes.each(function () {
var subnode = $(this);
var subnodeChildren = findChildren(subnode);
children = children.not(subnodeChildren);
});
//Change icon and hide/show children
if (tr.hasClass('collapse')) {
tr.removeClass('collapse').addClass('expand');
children.hide();
} else {
tr.removeClass('expand').addClass('collapse');
children.show();
}
return children;
});
});