what is querySelector js code example

Example 1: queryselector javascript

var element = document.querySelector("#myid .myclass p");

Example 2: queryselector for jquery

var x = $(".yourclass")[0];
console.log('jq' + x);
var y = document.querySelector(".yourclass");
console.log('js' + y);

Example 3: document.queryselector

<div id="foo\bar"></div>
<div id="foo:bar"></div>

<script>
  console.log('#foo\bar');               // "#fooar" (\b is the backspace control character)
  document.querySelector('#foo\bar');    // Does not match anything

  console.log('#foo\\bar');              // "#foo\bar"
  console.log('#foo\\\\bar');            // "#foo\\bar"
  document.querySelector('#foo\\\\bar'); // Match the first div

  document.querySelector('#foo:bar');    // Does not match anything
  document.querySelector('#foo\\:bar');  // Match the second div
</script>