Custom jQuery filter needs optimization

Question

In the code below, friendBlocks has 800+ items that look like this:

    Some Name
    &l         


        
      

Answer 1

This is noticeably much faster than your original code when tested in jsfiddle:

var blocks = $('div.block');
var foundBlocks = blocks.filter(function() {        
    return $('span.title', this).text().toLowerCase().indexOf(text) >= 0;
});    
foundBlocks.show();    
blocks.not(foundBlocks).hide();

JSFiddle Example

I tried changing it so it cloned and then did the show/hide but I didn't notice any obvious difference in speed. Although this was chrome, other browsers may be slower.