jQuery & jQuery UI Documentation

jQuery & jQuery UI

jQuery.noConflict()

jQuery.noConflict( [removeAll] ) Returns: Object

Description: Relinquish jQuery's control of the $ variable.

  • version added: 1.0jQuery.noConflict( [removeAll] )

    removeAllA Boolean indicating whether to remove all jQuery variables from the global scope (including jQuery itself).

Many JavaScript libraries use $ as a function or variable name, just as jQuery does. In jQuery's case, $ is just an alias for jQuery, so all functionality is available without using $. If we need to use another JavaScript library alongside jQuery, we can return control of $ back to the other library with a call to $.noConflict():

<script type="text/javascript" src="other_lib.js"></script>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript">
  $.noConflict();
  // Code that uses other library's $ can follow here.
</script>

This technique is especially effective in conjunction with the .ready() method's ability to alias the jQuery object, as within callback passed to .ready() we can use $ if we wish without fear of conflicts later:

<script type="text/javascript" src="other_lib.js"></script>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript">
  $.noConflict();
  jQuery(document).ready(function($) {
    // Code that uses jQuery's $ can follow here.
  });
  // Code that uses other library's $ can follow here.
</script>

If necessary, we can free up the jQuery name as well by passing true as an argument to the method. This is rarely necessary, and if we must do this (for example, if we need to use multiple versions of the jQuery library on the same page), we need to consider that most plug-ins rely on the presence of the jQuery variable and may not operate correctly in this situation.

Examples:

Example: Maps the original object that was referenced by $ back to $.

jQuery.noConflict();
// Do something with jQuery
jQuery("div p").hide();
// Do something with another library's $()
$("content").style.display = 'none';

Example: Reverts the $ alias and then creates and executes a function to provide the $ as a jQuery alias inside the functions scope. Inside the function the original $ object is not available. This works well for most plugins that don't rely on any other library.

jQuery.noConflict();
(function($) { 
  $(function() {
    // more code using $ as alias to jQuery
  });
})(jQuery);
// other code using $ as an alias to the other library

Example: You can chain the jQuery.noConflict() with the shorthand ready for a compact code.

jQuery.noConflict()(function(){
    // code using jQuery
}); 
// other code using $ as an alias to the other library

Example: Creates a different alias instead of jQuery to use in the rest of the script.

var j = jQuery.noConflict();
// Do something with jQuery
j("div p").hide();
// Do something with another library's $()
$("content").style.display = 'none';

Example: Completely move jQuery to a new namespace in another object.

var dom = {};
dom.query = jQuery.noConflict(true);

Result:

// Do something with the new jQuery
dom.query("div p").hide();
// Do something with another library's $()
$("content").style.display = 'none';
// Do something with another version of jQuery
jQuery("div > p").hide();