addclass jquery

$('some_element').addClass('some-class');

// You can add more than one class at one time
$('some_element').addClass('some-class another-class yet-another-class');

// Even thought jQuery allows you to do this
$('some_element').addClass('some-class').addClass('another-class').addClass('yet-another-class');

// That would be really wasteful, think of the planet!
// But more importantly, your RAM
// oh and those poor folks who be viewing your website

if ($( "#foo" ).hasClass('className')) {
	$( "#foo" ).removeClass( 'className');
} else {
  $( "#foo" ).addClass( 'className');
}

$("#elem").addClass("classname");

$( "p" ).addClass( "selected highlight" );

$( "p" ).addClass( "myClass yourClass" );

$( "p" ).removeClass( "myClass noClass" ).addClass( "yourClass" );

$("#my_id").attr("class", "my_new_class_name");