Roadmap › 4. Frontend › Step 46

jQuery

Selectors, traversal, DOM manipulation, events and delegation, effects, AJAX, deferreds, plugins, jQuery with ASP.NET MVC validation, performance and migrating from jQuery to modern JavaScript.

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Core

$(fn) DOM ready · $("css") select · $(el) wrap · $("<li>", {text}) create · chaining · implicit iteration · $.noConflict().

Traversal

find · filter · not · eq · first/last · parent/parents/closest · children/siblings/next/prev · is · has.

Manipulation

text · html · val · attr · prop · data · addClass/removeClass/toggleClass · css · append/prepend/after/before · appendTo · remove/detach/empty · clone.

Events

on(event, [selector], handler) · off · one · trigger · namespaces click.ns · e.preventDefault() · return false = prevent + stop.

AJAX

$.ajax({url, method, data, contentType, dataType}) · $.get · $.post · $.getJSON · .load() · .done/.fail/.always/.then · $.when · ajaxStart/ajaxStop.

Effects

show/hide/toggle · fadeIn/fadeOut/fadeToggle · slideUp/slideDown/slideToggle · animate · stop · delay.

Versions to remember

1.7 .on() · 1.9 removed .live() · 3.0 Promises/A+ · 3.5 XSS fix · 4.0 (2026) drops old IE, ES modules.

Modern equivalents

querySelector · classList · textContent · dataset · addEventListener + closest · fetch · CSS transitions.