// running code when the page loads $(document.ready(function(){ // code goes here }); // prevent caching ajax requests $.ajaxSetup({ cache: false }); // access the nth object (!as a jQuery object!) $('div').eq(0) $('div:eq(0)') // access the actual DOM element $('div')[0] $('div').get(0) // chaining $('div').hide().text('new content').addClass('updatedContent').show() // multiple selectors $('selector1, selector2, selector3').length // passing DOM elements in place of selectors $(document.getElementsByTagName('a')).length // second parameter is context (note that you can also use XHR request as context) $('input', document.forms[0]).length // filter - filters only among the current selection $('a').filter('.external').length // find - looks for elements below the selection $('p').find('em').length // use end() to go back to previous selections (follow markers from end() calls) $('p').filter('middle').find('span').end().end() // <<<--- if we did something here it would be on the p's // ^--------------------| // ^-----------------------------------------| // andSelf() includes current selection with previous $('div').find('p').andSelf().css('border', '1px solid') // prev(), next(), parent(), children(), nextAll(), prevAll() $('li:eq(3)').prev() // <<<--- element at eq(2) $('li:eq(3)').next() // <<<--- element at eq(4) $('li:eq(3)').parent() // <<<--- ul or ol element holding the li's $('li:eq(3)').parent().children() // <<<--- all li's in this list $('li:eq(3)').parent().children(':last') // <<<--- the last li in this list $('li:eq(3)').nextAll() // <<<--- all elements following eq(4) $('li:eq(3)').prevAll() // <<<--- all elements before eq(4) // trim whitespace from ends of a string value $.trim(' some string ') // show the value of the selected option in an input radio set $('input[name="somename"]:checked').val() // create html elements and add them to the page // see also: append(), prepend(), prependTo(), after(), before(), insertAfter(), insertBefore() // wrap(), wrapAll(), wrapInner() $('<p><a>jQuery</a></p>').find('a').attr('href', 'http://www.jquery.com').end().appendTo('body') // remove html elements from the page $('a.someclass').remove() // replacing elements $('span.original').replaceWith('<span>new</span>') $('<span>new</span>').replaceAll('span.original') // cloning elements $('span.someclass').clone().appendTo('body') // cloning elements, including events (passing true to clone()) // notice that this one adds a clone of a button, then removes the original $('button:first').clone(true).appendTo('body').end().end().remove()