…
Search Results |
||||
|---|---|---|---|---|
| # | id | tagName | className | outerHTML |
jQuery Selector Cheat Sheet — Click a row to apply the selector |
||
|---|---|---|
| Selector | Example $("pattern") | Notes |
| Basic | ||
| Wild Card | * | Returns ALL elements |
| Element | p | Returns all paragraph elements* <p>One</p> <p> Two</p> |
| ID | #MyID | Returns all elements with id of MyID: <div id="MyID"> </div> |
| Class | .MyClass | Returns all elements with css class of MyClass: <div class="MyClass"> </div> |
| Combinations | ||
| And | div, span | Returns all div AND span elements. The comma is the AND operator. |
| Child | div > span | Returns span elements directly inside a div. |
| Ancestor | div span | Returns all span elements inside a div. The space is the Ancestor operator. |
| Attributes | ||
| Attribute | [xyz] | Returns all elements with the attribute: <input xyz="abc" /> <div xyz="123" /> |
| Attribute Value | input[xyz=abc] | Returns all input elements with an attribute of xyz and value of abc: <input xyz="abc" /> |
| Attr$ | input[id$=abc] | Returns <input id="123abc" /> (ends with) |
| Attr^ | input[id^=abc] | Returns <input id="abc123" /> (starts with) |
| Attr* | input[id*=abc] | Returns <input id="123abc123" /> (contains) |
| Multiple | input[name=abc][value=yes] | Returns <input name="abc" value="yes" /> (both attributes/values present) |
| Missing | input:not([alt]) | Returns all input elements MISSING attribute alt |
| Misc | ||
| Checkbox | input[type=checkbox]:checked | Returns all checked checkboxes |
| Radio Button | input[type=radio]:not(:checked) | Returns all unchecked radio buttons |
| Selected | #MySelect :selected | Returns all Selected elements from element with id MySelect |
| Even items | #MyTable tr:even | Returns all even rows (can also use odd). Note: Even/Odd is zero based. |
| nth-child | #MyTable tr:nth-child(2) | Returns element by position, in this case the 2nd row in the table. Note: nth-position is 1 based. |
| Contains | p:contains("Hello") | Returns all paragraph elements that contain the text "Hello" |
| Lists | ||
| nth-child | li:nth-child(1) | Returns all li elements that are the first child of their parent |
| nth-child | li:nth-child(3) | Returns all li elements that are the third child of their parent |
| nth-child | li:nth-last-child(1) | Returns all li elements that are the first child of their parent, counting from the last li element |
…
The jQuery Selector starts with the dollar sign and parentheses – $(), and finds one or more HTML elements in the DOM. We can use name, id, CSS Class, type, attribute, etc to find elements using the jQuery Selector.
jQuery provides number of ways to select a specific DOM element(s). The following table lists the most important selector patterns.
| Category | Selector | Description |
|---|---|---|
| Find element | $('div') | Find all <div> elements |
| $('p, div, code') | Find <p>,<div> and <code> elements | |
| Find descendant elements | $('div p') | Find all <p> elements which are descendants of <div> |
| $('div > p') | Find <p> which is child of <div> | |
| $(*) | Find all elements | |
| Find by Id | $('#myDiv') | Find element whose id is myDiv |
| $('div#myDiv') | Find <div> element whose Id is myDiv | |
| $('#myDiv1, #myDiv2') | Find multiple elements by id separated by comma. | |
| Find by CSS class | $('.myCSSClass') | Find all the elements with class=myCSSClass. |
| $('.myCSSClass1, .myCSSClass2 ') | Finds all elements whose class attribute is set to myCSSClass1 or myCSSClass2 | |
| $('div.myCSSClass') | Finds all <div> elements with class=myCSSClass | |
| Find child element | $('p:first-child') | Find all <p> elements, which is the first child of its parent element. (parent element can be anything) |
| $("p:last-child") | Selects all <p> elements which is the last child of its parent element. (parent element can be anything) | |
| $("p:nth-child(5)") | Selects all <p> elements which is the 5th child of its parent element. (parent element can be anything) | |
| $("p:nth-last-child(2)") | Selects all <p> elements which is the 2nd last child of its parent element. (parent element can be anything) | |
| $("p:only-child") | Selects all <p> elements which is the only child of its parent element. (parent element can be anything) | |
| Find by attribute | $('[class]') | Find all the elements with the class attribute(whatever the value). |
| $('div[class]') | Find all the <div> elements that have a class attribute(whatever the value). | |
| Find by containing value of attribute | $('div[class=myCls]') | Find all the <div> elements whose class attributes are equal to myCls. |
| $('div[class|=myCls]') | Find all the <div> elements whose class attributes are either equal to myCls or starting with myCls string followed by a hyphen (-). | |
| $('div[class *="myCls"]') | Selects <div> elements whose class attributes contain myCls. | |
| $('div[class~=myCls]') | Selects div elements whose class attributes contain myCls, delimited by spaces. | |
| $("div[class $= 'myCls']") | Selects <div> elements whose class attribute value ends with myCls. The comparison is case sensitive. | |
| $("div[class != 'myCls']") | Selects <div> elements which do not have class attribute or value does not equal to myCls. | |
| $("div[class ^= 'myCls']") | Selects <div> elements whose class attribute value starts with myCls. | |
| $("div:contains('tutorialsteacher')" | Selects all <div> elements that contains the text 'tutorialsteacher' | |
| Find by input type | $(":input") | Selects all input elements. |
| :button | $(":button") | Selects all input elements where type="button". |
| :radio | $(":radio") | Selects all input types where type="radio" |
| :text | $(":text") | Selects all input elements where type="text" |
| ":checkbox" | $(":checkbox") | Selects all checkbox elements. |
| :submit | $(":submit") | Selects all input elements where type="submit". |
| :password | $(":password") | Selects all input elements where type="password". |
| :reset | $(":reset") | Selects all input elements where type="reset". |
| :image | $(':image') | Selects all input elements where type="image". |
| :file | $(':file') | Selects all input elements where type="file". |
| :enabled | $(':enabled') | Selects all enabled input elements. |
| :disabled | $(':disabled') | Selects all disabled input elements. |
| :selected | $(':selected') | Selects all selected input elements. |
| :checked | $(':checked') | Selects all checked input elements. |
| :hidden | $(':hidden') | Selects all hidden elements. |
| :visible | $(':visible') | Selects all visible elements. |
| :odd | $('tr:odd') | Selects all odd rows. (1,3,5,7..) |
| :even | $('tr:even') | Selects all even rows.(0,2,4,6..) |
Mastering advanced selector techniques can transform your coding workflow when you dive into jQuery. This section explores how you can leverage complex selectors—such as attribute selectors, pseudo-class selectors, and combinator selectors—to pinpoint elements precisely. You will learn how chaining selectors and applying filters can help you handle intricate DOM structures and dynamic content effectively. By understanding these sophisticated techniques, you can write cleaner, more maintainable code that targets exactly what you need. This approach saves you time and boosts your web applications' overall performance by reducing unnecessary DOM traversals. Mastering these advanced techniques is essential for developers who want to harness the full power of jQuery.
Optimizing the performance of your jQuery selectors is key to building fast, responsive web applications. In this section, you’ll discover strategies to refine your code for better efficiency. By learning how to reduce excessive DOM traversals and cache frequently accessed elements, you can dramatically improve page load times and user experience. We also delve into the importance of using efficient selector syntax and minimizing the use of overly generic selectors that may slow down your application. Alongside these tips, you’ll gain insights into benchmarking and profiling your jQuery code with tools like Chrome DevTools. With these performance optimization techniques at your disposal, you’ll be well-equipped to streamline your code and create a more robust, high-performing web experience.
Even the most experienced developers encounter challenges when their jQuery selectors don’t behave as expected. This section is dedicated to debugging and troubleshooting techniques that help you pinpoint and resolve common selector issues. You’ll learn how to use browser developer consoles, inspect elements, and apply jQuery’s built-in debugging methods to track down problematic code. Additionally, we discuss third-party plugins and debugging tools that can simplify the process. Understanding how to read error messages and trace your code flow is critical in ensuring your selectors operate reliably. With these practices, you’ll quickly identify performance bottlenecks or logical errors in your selectors, empowering you to maintain cleaner code and a smoother user experience throughout your projects.
Modern web applications often involve dynamic content and AJAX-driven updates that load elements after the initial page render. This section explores strategies for using jQuery selectors effectively in these scenarios. You will learn how to bind events to dynamically added elements using event delegation, ensuring that your interactive components remain functional as new content appears. We also discuss techniques for reapplying or updating selectors when AJAX calls inject fresh content into the DOM. By adopting these methods, you’re able to build applications that are both robust and responsive to real-time data changes. This comprehensive guide helps you master the art of managing asynchronous content while maintaining optimal performance and interactivity across your website.
Even in an era of modern frameworks like Angular, React, and Vue.js, jQuery still has its place in web development. This section discusses how you can integrate jQuery selectors into projects that use these frameworks without creating conflicts. You’ll discover best practices for using jQuery alongside modern libraries, ensuring that each tool operates in its optimal domain. This integration strategy enables you to take advantage of jQuery’s simplicity and rich plugin ecosystem while benefiting from the structured architecture of contemporary frameworks. Whether enhancing legacy projects or building new applications, understanding how to blend these technologies can lead to more flexible, maintainable code and a smoother transition between different development paradigms.
Understanding the differences between jQuery selectors and native DOM methods—like document.querySelector and document.querySelectorAll—is essential for any developer. In this section, you’ll explore a detailed comparison that highlights the strengths and limitations of each approach. You’ll learn when it makes sense to use jQuery for its ease of use and cross-browser compatibility and when native methods might offer better performance and more direct control. This analysis includes discussing browser support, performance benchmarks, and code readability. You can make informed decisions that best suit your project’s needs by weighing these factors. Whether you’re working on a small script or a large-scale application, understanding these differences helps you choose the right tool for each job.
Security is a critical aspect of web development, and careful use of jQuery selectors is no exception. In this section, you’ll learn about the common security pitfalls that can arise when using selectors in dynamic environments. We cover best practices for validating and sanitizing user input to avoid vulnerabilities such as cross-site scripting (XSS) attacks. Additionally, you’ll gain insights into safe coding techniques that help prevent code injection and unauthorized access to sensitive elements. This comprehensive guide emphasizes the importance of writing secure, maintainable code and integrating security measures from the ground up. By adhering to these practices, you protect your web applications and build trust with your users, ensuring that their interactions and data remain secure.
As web technologies evolve, so do the tools for DOM manipulation. In this section, we take a forward-looking perspective on the future of jQuery selectors in a landscape that increasingly favors modern JavaScript frameworks and native APIs. You’ll explore emerging trends, such as the rise of lightweight libraries and the enhanced capabilities of vanilla JavaScript with features like query selectors and modern event handling. We also discuss how CSS selectors evolve with browser advancements, providing more efficient ways to style and interact with web elements. By understanding these trends, you can prepare for a future where jQuery coexists with new technologies, helping you create hybrid solutions that combine the best of both worlds. Staying current with these developments will ensure that your skills remain relevant and your projects are built on cutting-edge practices.
Companies spend millions of dollars on firewalls, encryption and secure access devices, and it’s money wasted, because none of these measures address the weakest link in the security chain.
…