getElementById vs. querySelector (v253)

Revision 253 of this benchmark created on

Preparation HTML

<p id="foo">Foo</p>
<p id="bar">Bar</p>
<p id="baz">Baz</p>

Setup

var idSelectorRegexp = /^#[a-zA-Z]+[a-zA-Z0-9_\-]*$/;
  
  var select = function(query){
    // pure ID selector?
    if (idSelectorRegexp.test(query))
      return document.getElementById(query.slice(1));
    else
      return document.querySelector(query);
  };
  
  var select2 = function(query){
    // pure ID selector?
    if (query.startsWith("#"))
      return document.getElementById(query.slice(1));
    else
      return document.querySelector(query);
  };
  
  var select3 = function(query){
    // pure ID selector?
    if (query[0] === "#")
      return document.getElementById(query.slice(1));
    else
      return document.querySelector(query);
  };

Test runner

Ready to run.

Testing in
TestOps/sec
getElementById
var bar = document.getElementById("bar");
ready
querySelector
var bar = document.querySelector("#bar");
ready
mapping to getElementById
var bar = select("#bar");
ready
mapping with startsWith to getElementById
var bar = select2("#bar");
ready
mapping with [0] === "#" to getElementById
var bar = select3("#bar");
ready

Revisions

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