title: Speeding up window resize function performance
body: <p>I have some script similar to the following:</p>
  
  <pre><code>var breakpoints = [0,240,480,960,9999],
      bpCount = breakpoints.length,
      windowsize = 0;
  
  window.onresize = function() {
  
      windowsize = document.body.clientWidth;
  
      for(var i=0; i&lt;bpCount; i++) {
          if(windowsize &gt;= breakpoints[i] &amp;&amp; windowsize &lt; breakpoints[i+1]) {
              doSomething(breakpoints[i]);
              break;
          }
      }    
  
  };
  </code></pre>
  
  <p>However this seems to run pretty slowly, even in Chrome on a decent PC, and even when 'doSomething' is just performing a 'console.log', so I was just wondering if there was any better way of checking whether the screen size is between two values as it resizes?</p>
  
  <p>Thanks</p>