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Posts Tagged ‘JQuery’

PHP – HTML5

August 18, 2016 Leave a comment

 

PHP

Starting with PHP 5, the object model was rewritten to allow for better performance and more features. This was a major change from PHP 4. PHP 5 has a full object model.

features in PHP 5 are the inclusions of visibility, abstract and final classes and methods, additional magic methods, interfaces, cloning and typehinting.

PHP treats objects in the same way as references or handles, meaning that each variable contains an object reference rather than a copy of the entire object. See Objects and References

Features

Visibility : The visibility of a property or method can be defined by prefixing the declaration with the keywords public, protected or private.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

HTML

How do you improve the performance of a website.

  1. code unification :Each CSS file must be loaded before the page can be displayed in an internet browser.
  2. compress css and javascript files:We can compress a CSS file by removing unnecessary spaces, comments,
  3. Using sprite images instead of multiple images
  4. Always put javascripts at the bottom of the page.

What is bootstrap ?

Bootstrap is CSS framework for developing responsive, mobile first projects on the web. Current version of bootstrap is v3.3.6.  Bootstrap also comes with two preprocessors: less and saas.

 

Bootstrap uses 12 column grid system. Bootstrap’s grid system is responsive, and the columns will re-arrange depending on the screen size

 

What new features has been added in bootstrap 3?

  1. New Glyphicons icon font!
  2. Smallest file size.
  3. New grid system.
  4. its uses CSS compressors (Less/Saas)

Difference between container and container-fluid in bootstrap?

.container has a max width pixel value, whereas .container-fluid is max-width 100%.

.container-fluid continuously resizes as you change the width of your window/browser by any amount.

.container resizes in chunks at several certain widths, controlled by media queries (technically we can say it’s “fixed width”

because pixels values are specified, but if you stop there, people may get the

impression that it can’t change size – i.e. not responsive.)

 

Tell me latest jquery version ?

Latest version of jquery is  V-3.1.0 (11-8-2016)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Difference between html5 tag and normal tag ?

HTML5 tag are called as semantic tags.

A semantic element clearly describes its meaning to both the browser and the developer.

<article>

<aside>

<details>

<figcaption>

<figure>

<footer>

<header>

<main>

<mark>

<nav>

<section>

<summary>

<time>

 

Difference between live and bind function in jquery.

 

The bind() method attaches one or more event handlers for selected elements, and specifies a function to run when the event occurs.

 

The live() method was deprecated in jQuery version 1.7, and removed in version 1.9. Use the on() method instead.

 

Some new fautures of css3?

 

  1. border-radius (border-radius: 25px;)
  2. box-shadow (box-shadow:3px 3px 3px 2px #797979;)
  3. Text Shadow ( text-shadow: #aaa 2px 2px 2px;)
  4. Multiple Backgrounds

.container {

/* fallback */

background: url(image/bg1.png) no-repeat;

 

/* modern browsers */

background: url(image/bg1.png) 0 0 no-repeat,

url(image/bg2.png) 100% 0 no-repeat;

}

 

 

 

 

 

 

 

 

 

  1. Transition

We can add animation to an element using transition. We need to specify these parameters.

  1. transition-property
  2. transition-duration
  3. transition-timing-function
  4. transition-delay

 

div {

width: 150px;

height: 150px;

background: red;

/* For Safari 3.1 to 6.0 */

-webkit-transition-property: height;

-webkit-transition-duration: 2s;

-webkit-transition-timing-function: ease-in-out;

-webkit-transition-delay: 1s;

/* Standard syntax */

transition-property: height;

transition-duration: 2s;

transition-timing-function: linear;

transition-delay: 1s;

}

 

what is closest in jquery ? What’s the difference between .closest() and .parents(‘selector’)?

.closest() method begins its search with the element itself before progressing up the DOM tree, and stops when current element matches the selector.

.parents() Begins with the parent element, get the parent of each element in the current set of matched elements

What is json?

JSON stands for JavaScript Object Notation. JSON is language independent, lightweight data interchange format. JSON data is written as key value pairs.

Eg :”name”:”Selva”

Explain position property in css?

The CSS positioning properties allow you to position an element. There are four different positioning methods: Static, Fixed, relative, absolute.

 

 

 

Difference between $(this) and this in jquery?

Keyword ‘this’ is a native DOM element. $(this) is a jQuery object that allows you to call functions such as .addClass() on it.

Will HTML5 canvas supported in IE ?

HTML5 canvas is not supported in IE version less than 9. ExplorerCanvas(excanvas) a JS library is the option to render HTML5 canvas for IE6, 7, and 8.

what is jsonp?

JSONP is nothing but JSON with padding. JSONP is mostly used in RESTFull APIs(Cross domain request). JSONP is a simple trick to overcome XMLHttpRequest same domain policy. (As you know one cannot send AJAX (XMLHttpRequest) request to a different domain.). JSONP request appends the callback function with URL. Eg: http://www.abcs.com/example.php?callback=simplecallback

Whenever the server receives the callback it will return the data. The data can be accessed using that call back function.

A simple implementation of JSONP request.

//

(function() {

var flickerAPI = “http://api.flickr.com/services/feeds/photos_public.gne?jsoncallback=?&#8221;;

$.getJSON( flickerAPI, {

tags: “mount rainier”,

tagmode: “any”,

format: “json”

})

.done(function( data ) {

$.each( data.items, function( i, item ) {

$( “” ).attr( “src“, item.media.m ).appendTo( “#images” );

if ( i === 3 ) {

return false;

}

});

});

})();

// ]]>

 

 

 

How do you create a simple plugin in jquery?

Sample plugin creation code is given below:

(function($){

$.fn.showLinkLocation = function() {

return this.filter(‘a’).each(function(){

$(this).append(

‘ (‘ + $(this).attr(‘href’) + ‘)’

);

});

};

}(jQuery));

 

// Usage example:

$(‘a’).showLinkLocation();

 

List out some CSS Frameworks for creating responsive templates?

Bootstrap

-> Bootstrap is mobile first framework. It includes predefined classes for easy layout options, as well as powerful mixins for generating more semantic layouts.

 

Foundation 3

-> Foundation 3 is built with Sass, a powerful CSS preprocessor. “Pricing Tables” is an interesting componenet in foundation 3. Pricing tables are suitable for marketing site for a subscription-based product. It also offers super cool features like Right-to-left text direction support.

 

Skeleton

Skeleton is a small collection of CSS files that can help to rapidly develop sites that look beautiful at any size, be it a 17″ laptop screen or an iPhone.

 

YAML 4

YAML 4 is built on SAAS. You can check the documentation in the above link.

 

ResponsiveAeon

Responsive Aeon is a simple, fast, Intuitive css framework. It contains almost 120 lines of code and only 1kb minified.

 

 

 

 

 

What is the difference between canvas and svg?

<canvas> is an HTML element which can be used to draw graphics using JavaScript. This can be used to draw graphs, create animations etc.

The <canvas> element is not supported in older browsers, but is supported in recent versions of all major browsers.

The default size of the canvas is 300 px × 150 px (width × height). But custom sizes can be defined using the HTML height and width property.  The declaration is as follows.

<canvas id=”animate” width=”250″ height=”250″></canvas>

SVG stands for Scalable Vector Graphics (SVG) is based on XML markup language, for describing 2D vector graphics.

Can you explain the difference between cookies, sessionStorage and localStorage.?

LocalStorage stores data with no expiration date, and gets cleared only through JavaScript, or clearing the Browser Cache / Locally Stored Data – unlike cookie expiry.

Local storage and session storage are perfect for non sensitive data. The data stored in localStorage and sessionStorage can easily be read or changed from within the client/browser

so should not be relied upon for storage of sensitive or security related data within applications.

Data stored in the SessionStorage is only available for the duration of the browser session (and is deleted when the window is closed) – it does however survive page reloads.

In cookie, we can store 4096 bytes of data. Data stored in the cookie can be hacked by the user, unless the site uses SSL. We can also prevent injections like Cross-Site Scripting (XSS)/Script injection using httponly in the header.

Explain about quirks mode?

There are three modes used by the layout engines in web browsers: quirks mode, almost standards mode, and full standards mode.

Quirks mode is turned on when there is no correct DOCTYPE declaration, and turned off when there is a DOCTYPE definition.

However, invalid HTML – with respect to the chosen DOCTYPE – can also cause the browser to switch to quirks mode.

 

 

What is meant by hardware acceleration?

It means the graphical rendering is done on dedicated hardware (your GPU / graphics card) rather than your CPU. Hardware acceleration generally produces more fluid animation.In general you should always enable hardware acceleration as it will result in better performance of your application.

This will usually be a higher frame rate (the number of images displayed per second), and the higher the frame rate, the smoother the animation.

How can you load css resources conditionally?

Using CSS media querises we can load CSS contidionally. If you want to load the stylesheet for the device less than 600px, then you can declare as below.

<link rel=”stylesheet” media=”screen and (min-width: 600px)” href=”small.css”>

This style sheet will only load for screen size less than 600px.

Difference between article and section tag in HTML5. How can you nest them in your document?

The section element represents a generic section of a document or application. A section, in this context, is a thematic grouping of content, typically with a heading.

So basically the section element should contain related information bunched under a common heading.

The HTML5 <article> element represents a complete composition in a web page or web application that is independently distributable or reusable, e.g. in syndication.

This could be a forum post, a magazine or newspaper article, a blog entry, a user-submitted comment, an interactive widget or gadget, or any other independent item of content.

We can nest article inside a section tag and vice versa. This is completely legal interms of HTML5.

What happen when you dont use doctype?

When omitted, browsers tend to use a different rendering mode that is incompatible with some specifications.

Also HTML5 tags such as < article >,< footer >, < header >, < nav >, < section > may not be supported if the Doctype is not declared.

 

 

 

 

What are data- attributes good for?

The data-* attributes is used to store custom data related to the page or application.The custom data can be used in JavaScript to complete events or animations.

Which set of definitions, HTML attributes or CSS properties, take precedence?

CSS properties take precedence over HTML attributes. If both are specified, HTML attributes will be displayed in browsers without CSS support but won’t have any effect in browsers with CSS support.

How do I eliminate the blue border around linked images?

in your CSS, you can specify the border property for linked images:

a img { border: none ; }

However, note that removing the border that indicates an image is a link makes it harder for users to distinguish quickly and easily which images on a web page are clickable.

 

Explain about HTML5 local storage ?

There are two ways to store data in HTML as objects locally :

 

  1. localStorage – store data across session acess
  2. sessionStorage – storing data for current session only

Data will be stored in key/value pair format.

example:

localStorage.empid=”420″;

sessionStorage.companyname = “Thiruvarur info tech ”;

 

explain CSS media queries ?

CSS media queries are used to develop responsive templates for different layout of screen, print, mobile , tablet or any other resolutions

 

CSS media queries can be added in 3 ways as like CSS style sheet :

 

Internal stylesheet :  <style type=”text/css”>

@media only screen and (max-width: 600px){

/* rules apply to the device resolution is 480px or less  */

}

</style>

Imported stylesheet :   @import “tablet.css”   (min-width: 800px) and (max-width: 1200px);

External stylesheet:  <link rel=”stylesheet” type=”text/css” href=”deskto.css” media=”screen and (min-width: 1200px), print and (min-resolution: 300dpi)” />

 

 

explain css inheritance ?

Inheritance propagates property values from parent elements to their children. The inherited value of a property on an element is the computed value of the property on the element’s parent element. For the root element, which has no parent element, the inherited value is the initial value of the property.

<div class=”firstClass secondClass thirdClass fourthClass ” > </div >

what is javascript inheritance ?

In simple terms, inheritance is the concept of one thing gaining the properties or behaviours of something else.

Inherited children inherit their parent’s behaviour To say A inherits from B, is saying that A is a type of B.

In JavaScript You must use a special object called prototype.

function Animal() {}; // This is the Animal *Type*

Animal.prototype.eat = function () {

alert(“All animals can eat!”);

};

 

function Bird() {}; // Declaring a Bird *Type*

Bird.prototype = new Animal(); // Birds inherit from Animal

Bird.prototype.fly = function() {

alert(“Birds are special, they can fly!”);

};

The effect of this is that any Birds you create (called an instance of Bird) all have the properties of Animals

var aBird = new Bird(); // Create an instance of the Bird Type

aBird.eat(); // It should alert, so the inheritance worked

aBird.fly(); // Important part of inheritance, Bird is also different to Animal

 

var anAnimal = new Animal(); // Let’s check an instance of Animal now

anAnimal.eat(); // Alerts, no problem here

anAnimal.fly(); // Error will occur, since only Birds have fly() in its prototype

 

explain javascript associative array ?

Associative arrays are where we can associate a key string with a value string

JavaScript objects are also associative arrays.

i.e the property  emp.Name can also be read by calling emp[‘Name’]

We can access each property by entering the name of the property as a string into the array

it refers to accessing the DOM elements of HTML also [as object or associative array]

 

 

 

explain JS Namespace ?

Namespacing is a technique employed to avoid collisions with other objects or variables in the global namespace

and also helps to organize blocks of functionality into easily manageable groups that can be uniquely identified.

JavaScript doesn’t  builtin support of namespacing but using objects and closures we can achieve a similar effect.

javascript Namespacing patterns :

1)    Single global variables :

var myApplication =  (function(){

function(){

/*…*/

},

return{

/*…*/

}

})();

 

2)    Object literal notation :

var myApplication = {

getInfo:function(){ /**/ },

// we can also populate our object literal to support

// further object literal namespaces containing anything

// really:

models : {},

views : {

pages : {}

},

collections : {}

};

 

 

 

 

 

 

3)    Nested namespacing :

var myApp =  myApp || {};

// perform a similar existence check when defining nested

// children

myApp.routers = myApp.routers || {};

myApp.model = myApp.model || {};

myApp.model.special = myApp.model.special || {};

// nested namespaces can be as complex as required

 

4)    Immediately-invoked Function Expressions :

// an (anonymous) immediately-invoked function expression

(function(){ /*…*/})();

// a named immediately-invoked function expression

(function foobar(){ /*..*/}());

// this is technically a self-executing function which is quite different

function foobar(){ foobar(); }

 

5)   Namespace injection :

// define a namespace we can use later

var ns = ns || {}, ns2 = ns2 || {};

// the module/namespace creator

var creator = function(val){

var val = val || 0;

this.next = function(){

return val++

};

 

this.reset = function(){

val = 0;

}

}

creator.call(ns);

 

// ns.next, ns.reset now exist

creator.call(ns2, 5000);

// ns2 contains the same methods

// but has an overridden value for val

// of 5000

 

 

 

 

Type of webservice ?

there are two types of web service….1. SOAP [Simple Object Access Protocol] Webservice and 2. RESTful [REpresentational State Transfer] Webservice.

SOAP is a messaging protocol , REST is a design philosophy , not a protocol.

SOAP:

you define your interface in a .wsdl file, which describes exactly which input parameters are expected and how the return values will look like

there are tools to generate the .wsdl files out of java class hirarchies. JAXB for example

there are also tools to generate java objects/classes as part of eclipse for example (don’t know the name in the moment).

SOAP is very strict. Every request is validatet against the wsdl before processing.

A good but not so easy to start with framework for SOAP WS is Apache CXF

 

REST:  (no hands on experience up to now, feel free to correct and improve 😉 ):

a way to access a webserver or web application to retrieve data from or send to it.

it’s only negotiated, how it is accessed.

common is something like this http://server.domain.com/app/type/id=123 to retrieve object of type type with id=123 very intuitive, but no automatic validation of requests.

The main advantages of REST web services are:

  1. Lightweight – not a lot of extra xml markup
  2. Human Readable Results
  3. Easy to build – no toolkits required

SOAP also has some advantages:

  1. Easy to consume – sometimes
  2. Rigid – type checking, adheres to a contract
  3. Development tools

 

 

 

What is namespacing?

In many programming languages, namespacing is a technique employed to avoid collisions with other objects or variables in the global namespace. They’re also extremely useful for helping organize blocks of functionality in your application into easily manageable groups that can be uniquely identified.Namespacing Fundamentals

  1. Single global variables
  2. Object literal notation
  3. Nested namespacing
  4. Immediately-invoked Function Expressions
  5. Namespace injection

 

Single global variables

One popular pattern for namespacing in JavaScript is opting for a single global variable as your primary object of reference. A skeleton implementation of this where we return an object with functions and properties can be found below:

var myApplication =  (function(){

function(){

/*…*/

},

return{

/*…*/

}

})();

Object literal notation

Object literal notation can be thought of as an object containing a collection of key:value pairs with a colon separating each pair of keys and values. It’s syntax requires a comma to be used after each key:value pair with the exception of the last item in your object, similar to a normal array.

var myApplication = {

getInfo:function(){ /**/ },

// we can also populate our object literal to support

// further object literal namespaces containing anything

// really:

models : {},

views : {

pages : {}

},

collections : {}

};

 

 

One can also opt for adding properties directly to the namespace:

myApplication.foo = function(){

return “bar”;

}

myApplication.utils = {

toString:function(){

/*..*/

},

export: function(){

/*..*/

}

}

 

  1. Nested namespacing
  2. Immediately-invoked Function Expressions (IIFE)s
  3. Namespace injection

 

  1. Explain about css specificity

 

  1. what is the use of box shadow and tell me the syntax.

 

  1. how to acheive rounded corners in css3.

 

  1. How will you improve the performance of a website.

 

  1. What is the use of sprite images.

 

  1. What are the different font formats and how will you include in your css stylesheet.

 

  1. What is responsive web page layout.

 

  1. What is fluid layout and advantages of it ?

 

  1. What do you know about css animations. Will you do css3 animation if we give google access?

 

  1. what are the css frameworks you know. have you ever used any css frameworks like LESS SAAS?

 

 

 

 

 

 

 

 

 

  1. Difference between HTML4 and HTML5?

 

  1. What is the use of canvas ? have you ever used it.

 

  1. What is the main difference between canvas and svg?

 

  1. What are semantic tags in html5. What is the main advantage of it.

 

 

 

  1. How will you add a jquery to your page.

 

  1. What is the diiference between javascript and jquery?

 

  1. Tell me the difference between document.ready and onload function in jquery?

 

  1. how can u apply css in jquery?

 

  1. Can you dynamicaaly add a div using jquery ?

 

  1. What are filters in jquery?

 

  1. What is an anonymous function in jquery and how will you define it?

 

  1. Have you ever heared about MVC in javascript?

 

  1. Javascript or Jquery which is faster ?

 

  1. How can you animate using Jquery?

 

  1. Tell me the use of is() , eq() methods in jquery?

 

  1. Why we use index() method in jquery.

 

  1. Tell me jquery.noConflict() method.

 

  1. Have you ever contributed any plugin?

 

  1. Tell me what are the Jquery UI you know. And how can you customize them.?

My Team Plugin for WordPress

December 19, 2013 1 comment

We are  happy to release “My Team” a new WordPress to display team/staff members. You can also display a set of pictures and information in different layouts.

Nowadays, WordPress is more than just a blog. And behind such website is a team. The plugin acknowledges those guys, by creating a template which anyone can copy in his theme directory and have a page ready for the people behind it. The plugin provides the administrator with a nice interface to add/edit/delete the team members. The plugin is under active development so keep checking the page. The plugin uses the short-code given at

http://wordpress.org/plugins/wp-my-team/

Features:

You can display the entries in 4 different main ways

  1. Grid view.
  2. Grid view with Information on hover.
  3. Table list view.
  4. Number of Columns.
  5. Image Shapes and effects.
  6. Text Align.
  7. Special Settings.
  8. Image Sizes.
  9. Email Settings.
  10. Single Page Settings.
  11. Auto Generation Shortcode & PHP Function.

screenshot

Jquery Timeago Implementation with PHP.

Nowadays timeago is the most important functionality in social networking sites, it helps to updating timestamps automatically. Recent days I received few requests from 9lessons readers that asked me how to implement timeago plugin with dynamic loading live data using PHP. In this post I am just presenting a simple tip to implement timeago in a better way.

Why Live Query
LiveQuery utilizes the power of jQuery selectors by binding events or firing callbacks for matched elements auto-magically, even after the page has been loaded and the DOM updated.

Code
Contains javascipt code. $(this).timeago()- here this element is refers to timeagoclass selector of the anchor tag.

 

// <![CDATA[
javascript” src=”js/jquery.min.js”>
// ]]>
// <![CDATA[
javascript” src=”js/jquery.livequery.js”>
// ]]>
// <![CDATA[
javascript” src=”js/jquery.timeago.js”>
// ]]>
<script type=”text/javascript”>
$(document).ready(function(){
$(“.timeago”).livequery(function() // LiveQuery
{
$(this).timeago(); // Calling Timeago Funtion
});
});
</script>

//HTML & PHP Code
<!–?php
$time=time(); // Current timestamp eg: 1371612613
$mtime=date(“c”, $time); // Converts to date formate 2013-06-19T03:30:13+00:00
?>

You opened this page <a href=’#’ class=’timeago’ title=”<!–?php echo$mtime; ?>“></a>

 

10 More Useful WordPress Code Snippets For Your Blog

July 6, 2012 1 comment

WordPress is the best open source sofware which is completely free to use.The advantage of being open source for a software is that developers can see its codes an write plugins to make it more functional.And also developers add or change small piece of codes especially in functions.php file to unleash the power of your favorite blogging engine.

In today’s post we are again sharing wordpress code snippets.I think you will find a useful wordpress code snippet for your wordpress blog.

You may also take a look at our past wordpress theme collections;

htaccess Gzip Compression

Add the following code in your .htaccess file.Gzip will drastically reduce HTTP response time.

# BEGIN GZIP

AddOutputFilterByType DEFLATE text/text text/html text/plain text/xml text/css application/x-javascript application/javascript

# END GZIP

Instructions:
Just add this to your .htaccess file. Gzip will drastically reduce HTTP response time.

How to Remove the Width and Height Attributes From WP Image Uploader

add_filter( ‘post_thumbnail_html’, ‘remove_width_attribute’, 10 );
add_filter( ‘image_send_to_editor’, ‘remove_width_attribute’, 10 );

function remove_width_attribute( $html ) {
$html = preg_replace( ‘/(width|height)=\”\d*\”\s/’, “”, $html );
return $html;
}

If you upload images via the WordPress image uploader and insert it into your post, it will include the image width and height attribute in the html tag. Here’s what it will look like.

In most cases, this is absolutely alright. However, if you are using a responsive theme or are dealing with responsive web design, the “width” and “height” attribute will be a major roadblock that you need to get rid of.

Here’s how you can do it.

1. Open your theme’s functions.php file.

2. Copy and paste the following code:
add_filter( ‘post_thumbnail_html’, ‘remove_width_attribute’, 10 );
add_filter( ‘image_send_to_editor’, ‘remove_width_attribute’, 10 );

function remove_width_attribute( $html ) {
$html = preg_replace( ‘/(width|height)=\”\d*\”\s/’, “”, $html );
return $html;
}

3. Save the changes.

That’s it. Next time when you insert image into the post via the WP image uploader, the width and height attribute will no longer be there.

How to Change the Font in HTML Editor In WordPress 3.3

add_action( ‘admin_head-post.php’, ‘wpdb_fix_html_editor_font’ );
add_action( ‘admin_head-post-new.php’, ‘wpdb_fix_html_editor_font’ );

function wpdb_fix_html_editor_font() { ?>

<!–?php }

Add/remove Contact Info Fields

To add or remove fields from this section, just add the following to your functions.php.

Login with Username or Email Address

Adding this snippet to the functions.php of your wordpress theme will let users login using an email address or a username. The second snippet will change the text on the login page from “username” to “username / email” but feel free to change the login text to anything you would like.

function login_with_email_address($username) {
$user = get_user_by(’email’,$username);
if(!empty($user->user_login))
$username = $user->user_login;
return $username;
}
add_action(‘wp_authenticate’,’login_with_email_address’);
function change_username_wps_text($text){
if(in_array($GLOBALS[‘pagenow’], array(‘wp-login.php’))){
if ($text == ‘Username’){$text = ‘Username / Email’;}
}
return $text;
}
add_filter( ‘gettext’, ‘change_username_wps_text’ );

Add PayPal Donate Button

Add this snippet to the functions.php to add ‘Donate’ Button on your WordPress Website

// paypal donate button
function cwc_donate_shortcode( $atts ) {
extract(shortcode_atts(array(
‘text’ => ‘Make a donation’,
‘account’ => ‘REPLACE ME’,
‘for’ => ”,
), $atts));
global $post;
if (!$for) $for = str_replace(” “,”+”,$post->post_title);
return ‘‘.$text.’‘;
}
add_shortcode(‘donate’, ‘cwc_donate_shortcode’);

How to Make a Slick Ajax Contact Form with jQuery and PHP

June 16, 2012 1 comment

Contact forms can be useful way for visitors to contact the owner of a site. They’re easy to use, and since they don’t expose the site owner’s email address in the page, they cut down on spam too.

However, contact forms can also be cumbersome, especially as they’re usually on a separate page. The visitor has to visit the contact form page, fill in the details, view yet another response page, and then try to make their way back to the page they were originally reading.

Fortunately, Ajax gives us a way round this problem. By embedding the form in the page, and submitting the form data via Ajax, the user never has to leave the current page. It also provides a smoother experience for the user.

In this tutorial we’ll build a nice-looking, embedded Ajax contact form that the user can summon up by clicking a link in the page. Along the way, we’ll explore various topics, including:

  • HTML5 form fields
  • How to use fallback techniques to make the form function even if the browser has JavaScript turned off
  • Using CSS techniques to create attractive forms
  • Writing a secure form mailer using PHP
  • Animating page elements with jQuery, and, of course…
  • Using jQuery to make Ajax requests

Before you begin, check out the finished product by clicking the View Demo button above. This opens a new page with some dummy content, and a couple of “Send us an email” links. Click one of these links to display the form.

Step 1: Create the markup

Let’s start with the HTML for our page. This includes the form itself — we’ll hide it initially using JavaScript when the page loads — and also some dummy content and a couple of “Send us an email” links that will display the form when clicked:

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<!doctype html>
<html lang="en">
<head>
<title>A Slick Ajax Contact Form with jQuery and PHP</title>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8">
</head>
<body>
<div id="content">
  <p style="padding-bottom: 50px; font-weight: bold; text-align: center;"><a href="#contactForm">~ Send us an email ~</a></p>
  <!-- Content here -->
  <p style="padding-top: 50px; font-weight: bold; text-align: center;"><a href="#contactForm">~ Send us an email ~</a></p>
 
</div>
<form id="contactForm" action="processForm.php" method="post">
  <h2>Send us an email...</h2>
  <ul>
    <li>
      <label for="senderName">Your Name</label>
      <input type="text" name="senderName" id="senderName" placeholder="Please type your name" required="required" maxlength="40" />
    </li>
    <li>
      <label for="senderEmail">Your Email Address</label>
      <input type="email" name="senderEmail" id="senderEmail" placeholder="Please type your email address" required="required" maxlength="50" />
    </li>
    <li>
      <label for="message" style="padding-top: .5em;">Your Message</label>
      <textarea name="message" id="message" placeholder="Please type your message" required="required" cols="80" rows="10" maxlength="10000"></textarea>
    </li>
  </ul>
  <div id="formButtons">
    <input type="submit" id="sendMessage" name="sendMessage" value="Send Email" />
    <input type="button" id="cancel" name="cancel" value="Cancel" />
  </div>
</form>
<div id="sendingMessage" class="statusMessage"><p>Sending your message. Please wait...</p></div>
<div id="successMessage" class="statusMessage"><p>Thanks for sending your message! We'll get back to you shortly.</p></div>
<div id="failureMessage" class="statusMessage"><p>There was a problem sending your message. Please try again.</p></div>
<div id="incompleteMessage" class="statusMessage"><p>Please complete all the fields in the form before sending.</p></div>
</body>
</html>

I’ve omitted the dummy content in the above code, since it’s not relevant to the tutorial.

The form sends its data to a processForm.php script that does the actual emailing. (We’ll write this PHP script in a moment.) By setting the form’s action attribute to "processForm.php", we ensure that the form is usable even with JavaScript disabled. Later, our JavaScript will read this action attribute so that it knows where to send the Ajax request.

The form itself uses some HTML5 form features such as placeholders, the email field type, and the required attribute to ensure that all the fields have been filled in. We’ll also add JavaScript validation for browsers that don’t yet support HTML5 validation.

Step 2: Add the CSS

Screenshot of styled form

Now we’ll add the CSS to our HTML page in order to style the page and form. The bulk of the CSS positions the form and status messages in the centre of the window, and styles the form and form fields.

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<style type="text/css">
/* Add some margin to the page and set a default font and colour */
body {
  margin: 30px;
  font-family: "Georgia", serif;
  line-height: 1.8em;
  color: #333;
}
/* Set the content dimensions */
#content {
  width: 800px;
  padding: 50px;
  margin: 0 auto;
  display: block;
  font-size: 1.2em;
}
#content h2 {
  line-height: 1.5em;
}
/* Add curved borders to various elements */
#contactForm, .statusMessage, input[type="submit"], input[type="button"] {
  -moz-border-radius: 10px;
  -webkit-border-radius: 10px
  border-radius: 10px;
}
/* Style for the contact form and status messages */
#contactForm, .statusMessage {
  color: #666;
  background-color: #ebedf2;
  background: -webkit-gradient( linear, left bottom, left top, color-stop(0,#dfe1e5), color-stop(1, #ebedf2) );
  background: -moz-linear-gradient( center bottom, #dfe1e5 0%, #ebedf2 100% ); 
  border: 1px solid #aaa;
  -moz-box-shadow: 0 0 1em rgba(0, 0, 0, .5);
  -webkit-box-shadow: 0 0 1em rgba(0, 0, 0, .5);
  box-shadow: 0 0 1em rgba(0, 0, 0, .5);
  opacity: .95;
}
/* The form dimensions */
#contactForm {
  width: 40em;
  height: 33em;
  padding: 0 1.5em 1.5em 1.5em;
  margin: 0 auto;
}
/* Position the form in the middle of the window (if JavaScript is enabled) */
#contactForm.positioned {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  margin-top: auto;
  margin-bottom: auto;
}
/* Dimensions and position of the status messages */
.statusMessage {
  display: none;
  margin: auto;
  width: 30em;
  height: 2em;
  padding: 1.5em;
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
}
.statusMessage p {
  text-align: center;
  margin: 0;
  padding: 0;
}
/* The header at the top of the form */
#contactForm h2 {
  font-size: 2em;
  font-style: italic;
  letter-spacing: .05em;
  margin: 0 0 1em -.75em;
  padding: 1em;
  width: 19.5em
  color: #aeb6aa;
  background: #dfe0e5 url('images/stamp.jpg') no-repeat 15em -3em; /* http://morguefile.com/archive/display/606433 */
  border-bottom: 1px solid #aaa;
  -moz-border-radius: 10px 10px 0 0;
  -webkit-border-radius: 10px 10px 0 0
  border-radius: 10px 10px 0 0;
}
/* Give form elements consistent margin, padding and line height */
#contactForm ul {
  list-style: none;
  margin: 0;
  padding: 0;
}
#contactForm ul li {
  margin: .9em 0 0 0;
  padding: 0;
}
#contactForm input, #contactForm label {
  line-height: 1em;
}
/* The field labels */
label {
  display: block;
  float: left;
  clear: left;
  text-align: right;
  width: 28%;
  padding: .4em 0 0 0;
  margin: .15em .5em 0 0;
  font-weight: bold;
}
/* The fields */
input, textarea {
  display: block;
  margin: 0;
  padding: .4em;
  width: 67%;
  font-family: "Georgia", serif;
  font-size: 1em;
  border: 1px solid #aaa;
  -moz-border-radius: 5px;
  -webkit-border-radius: 5px;   
  border-radius: 5px;
  -moz-box-shadow: rgba(0,0,0,.2) 0 1px 4px inset;
  -webkit-box-shadow: rgba(0,0,0,.2) 0 1px 4px inset;
  box-shadow: rgba(0,0,0,.2) 0 1px 4px inset;
  background: #fff;
}
textarea {
  height: 13em;
  line-height: 1.5em;
  resize: none;
}
/* Place a border around focused fields, and hide the inner shadow */
#contactForm *:focus {
  border: 1px solid #66f;
  outline: none;
  box-shadow: none;
  -moz-box-shadow: none;
  -webkit-box-shadow: none;
}
/* Display correctly filled-in fields with a green background */
input:valid, textarea:valid {
  background: #dfd;
}
/* The Send and Cancel buttons */
input[type="submit"], input[type="button"] {
  float: right;
  margin: 2em 1em 0 1em;
  width: 10em;
  padding: .5em;
  border: 1px solid #666;
  -moz-border-radius: 10px;
  -webkit-border-radius: 10px
  border-radius: 10px;
  -moz-box-shadow: 0 0 .5em rgba(0, 0, 0, .8);
  -webkit-box-shadow: 0 0 .5em rgba(0, 0, 0, .8);
  box-shadow: 0 0 .5em rgba(0, 0, 0, .8);
  color: #fff;
  background: #0a0;
  font-size: 1em;
  line-height: 1em;
  font-weight: bold;
  opacity: .7;
  -webkit-appearance: none;
  -moz-transition: opacity .5s;
  -webkit-transition: opacity .5s;
  -o-transition: opacity .5s;
  transition: opacity .5s;
}
input[type="submit"]:hover,
input[type="submit"]:active,
input[type="button"]:hover,
input[type="button"]:active {
  cursor: pointer;
  opacity: 1;
}
input[type="submit"]:active, input[type="button"]:active {
  color: #333;
  background: #eee;
  -moz-box-shadow: 0 0 .5em rgba(0, 0, 0, .8) inset;
  -webkit-box-shadow: 0 0 .5em rgba(0, 0, 0, .8) inset;
  box-shadow: 0 0 .5em rgba(0, 0, 0, .8) inset;
}
input[type="button"] {
  background: #f33;
}
/* Header/footer boxes */
.wideBox {
  clear: both;
  text-align: center;
  margin: 70px;
  padding: 10px;
  background: #ebedf2;
  border: 1px solid #333;
}
.wideBox h1 {
  font-weight: bold;
  margin: 20px;
  color: #666;
  font-size: 1.5em;
}
</style>
<!-- Some IE7 hacks and workarounds -->
<!--[if lt IE 8]>
<style>
/* IE7 needs the fields to be floated as well as the labels */
input, textarea {
  float: right;
}
#formButtons {
  clear: both;
}
/*
  IE7 needs an ickier approach to vertical/horizontal centring with fixed positioning.
  The negative margins are half the element's width/height.
*/
#contactForm.positioned, .statusMessage {
  left: 50%;
  top: 50%;
}
#contactForm.positioned {
  margin-left: -20em;
  margin-top: -16.5em;
}
.statusMessage {
  margin-left: -15em;
  margin-top: -1em;
}
</style>
<![endif]-->

Let’s look at some interesting sections of the CSS:

  1. Style for the contact form and status messages
    We give the form and status boxes a nice gentle top-to-bottom gradient using -webkit-gradient and -moz-linear-gradient, and we also add a drop shadow with box-shadow (and its vendor-specific variants). Finally, we give the form and message boxes an opacity of .95 (95%), which makes the page content just show through — a nice subtle effect.
  2. Position the form in the middle of the window (if JavaScript is enabled)
    Initially, we simply place the form inline after the page content. This is so that the form can be used for non-JavaScript-enabled browsers without getting in the way of the content. However, for JavaScript browsers, we want the form to appear in the centre of the window, over the top of the content.Our #contactForm.positioned rule does just that. It uses fixed positioning, sets the top, bottom, left and right values all to zero, and ensures that all 4 margins are set to auto. This centres the element both horizontally and vertically in most modern browsers. Later we’ll use our JavaScript to add the positionedclass to the form.We also position the status message boxes in the same way.
  3. The header at the top of the form
    Our form includes a nice “Send us an email…” header with an image of a postage stamp. Our #contactForm h2rule styles this header. We give the text a large italic style and space the letters out slightly. We also add margin and padding to create space around and inside the header. We use some negative left margin (-.75em) on the header to bypass the padding on the form, so that the header goes right to the left edge of the form. We also set the width of the header to 19.5em so that it exactly matches the width of the form.Why -.75em and 19.5em? Because ems cascade, and we’ve set our font size to 2em. So -.75em actually becomes -1.5em (the width of the form’s padding), and 19.5em becomes 39em (the width of the form, minus 1em for the h2‘s padding). Phew! Maybe I’ll use pixels next time… :)We also set the heading’s colour, give it a dark background, position the postage stamp image in the top right corner, add a thin bottom border, and add curved top corners.
  4. The fields
    We give the input and textarea fields an attractive font, a rounded border using border-radius, and a gentle inner shadow using box-shadow. We also float the field labels left so that they sit alongside the fields. When a field is focused (clicked on or moved to with the Tab key), we give it a blue border and remove the shadow. We also set outline: none to remove the blue outline added by some browsers. Finally, we use the :valid pseudo-class to give correctly completed fields a green background, for those browsers that support HTML5 form validation.
  5. The Send and Cancel buttons
    input[type="submit"] selects the Send Email button, while input[type="button"] selects the Cancel button. We float them right to position them side by side, and add some margin to give them space. We give them a fixed width, and some padding to make them a decent size. We add a rounded border and subtle drop shadow, and specify text and background colours. We also make the buttons slightly transparent (opacity: .7), and make them fully transparent when hovered over to highlight them. We use a CSS transition to fade the opacity slowly. Finally, when the buttons are clicked (:active) we move the shadow inside the buttons to give a “pressed” appearance, and give them a black-on-white colour scheme.

Step 3: Build the PHP form mailer

We’ve now created our form page, and styled the form. The next step is to build a short PHP script to actually send the email messages. This script will reside on the web server. When the user submits the form, the form’s data is sent to the PHP script, which then sends the email and returns a response indicating whether or not the email was sent successfully.

Here’s the PHP script — call it processForm.php, and save it in the same folder as the form page you created in Steps 1 and 2:

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<?php
// Define some constants
define( "RECIPIENT_NAME", "John Smith" );
define( "RECIPIENT_EMAIL", "john@example.com" );
define( "EMAIL_SUBJECT", "Visitor Message" );
// Read the form values
$success = false;
$senderName = isset( $_POST['senderName'] ) ? preg_replace( "/[^\.\-\' a-zA-Z0-9]/", "", $_POST['senderName'] ) : "";
$senderEmail = isset( $_POST['senderEmail'] ) ? preg_replace( "/[^\.\-\_\@a-zA-Z0-9]/", "", $_POST['senderEmail'] ) : "";
$message = isset( $_POST['message'] ) ? preg_replace( "/(From:|To:|BCC:|CC:|Subject:|Content-Type:)/", "", $_POST['message'] ) : "";
// If all values exist, send the email
if ( $senderName && $senderEmail && $message ) {
  $recipient = RECIPIENT_NAME . " <" . RECIPIENT_EMAIL . ">";
  $headers = "From: " . $senderName . " <" . $senderEmail . ">";
  $success = mail( $recipient, EMAIL_SUBJECT, $message, $headers );
}
// Return an appropriate response to the browser
if ( isset($_GET["ajax"]) ) {
  echo $success ? "success" : "error";
} else {
?>
<html>
  <head>
    <title>Thanks!</title>
  </head>
  <body>
  <?php if ( $success ) echo "<p>Thanks for sending your message! We'll get back to you shortly.</p>" ?>
  <?php if ( !$success ) echo "<p>There was a problem sending your message. Please try again.</p>" ?>
  <p>Click your browser's Back button to return to the page.</p>
  </body>
</html>
<?php
}
?>

This script is fairly straightforward. Let’s break it down:

    1. Define some constants
      First we define some config options for the name and email address of the person who will receive the email message. (Change these to your own name and email address.) We also set a subject for the message.
    2. Read the form values
      Next we check for our 3 form fields, senderName, senderEmail and message, in the posted form data. For each field, we check if it exists. If it does then we pass its value through a regular expression to remove any potentially malicious characters that a spammer might try to use, and store the result in a variable. If it doesn’t exist then we set the variable to an empty value.
    3. If all values exist, send the email
      If the 3 field values all contain data then we send the email. First we construct the recipient string from the recipient name and email address. Then we add a "From:" header to the message using the name and email address that the visitor entered in the form. This is the “From:” value that the recipient will see in their email program. Finally, we use the PHP mail() function to send the email message, storing the return value in the variable $success. (mail() returns true if it managed to send the email, or false otherwise.)
    4. Return an appropriate response to the browser
      Once we’ve attempted to send the email, we send a “success” or “error” message back to the browser as appropriate. If the request URL contained an "ajax" parameter then we know the form was submitted via Ajax using our JavaScript code, so we simply return the value "success" or "error"to the JavaScript, which will then display an appropriate message to the user. However, if the form was submitted without using Ajax then the user must have JavaScript turned off in their browser. In this situation, we display a more helpful error message in the browser, with instructions to the user to use their Back button to return to the page.Our JavaScript will add the ajax parameter to the URL when it submits the form, as you’ll see in Step 6.

Step 4: Include the jQuery library and set the delay

Our form is actually functional now. You can open the page in a browser, click the “Send us an email” link to jump to the form, fill in the fields, and submit the form to send the message.

However, we’re now going to enhance our form using JavaScript to make the experience nicer for the user.

We’ll use jQuery to do most of the heavy lifting, so the first step is to include the jQuery library in the page’s head element:

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<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.1/jquery.min.js"></script>

Here we’ve linked directly to the jQuery library on Google’s CDN, but you can download the library and host it on your own server if you prefer.

We’ll also add a global config variable, messageDelay, to control how long the message boxes appear on the screen. This value is in milliseconds. Feel free to change it to a shorter or longer time:

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<script type="text/javascript">
var messageDelay = 2000;  // How long to display status messages (in milliseconds)

Step 5: Write the init() function

The first stage of our form-enhancing JavaScript is the init() function. This sets up the form so that it can be shown and hidden on demand, and also modifies the form so that it will be submitted using our JavaScript, rather than sent natively by the browser.

Here’s the code:

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// Init the form once the document is ready
$( init );
// Initialize the form
function init() {
  // Hide the form initially.
  // Make submitForm() the form’s submit handler.
  // Position the form so it sits in the centre of the browser window.
  $('#contactForm').hide().submit( submitForm ).addClass( 'positioned' );
  // When the "Send us an email" link is clicked:
  // 1. Fade the content out
  // 2. Display the form
  // 3. Move focus to the first field
  // 4. Prevent the link being followed
  $('a[href="#contactForm"]').click( function() {
    $('#content').fadeTo( 'slow', .2 );
    $('#contactForm').fadeIn( 'slow', function() {
      $('#senderName').focus();
    } )
    return false;
  } );
  
  // When the "Cancel" button is clicked, close the form
  $('#cancel').click( function() {
    $('#contactForm').fadeOut();
    $('#content').fadeTo( 'slow', 1 );
  } ); 
  // When the "Escape" key is pressed, close the form
  $('#contactForm').keydown( function( event ) {
    if ( event.which == 27 ) {
      $('#contactForm').fadeOut();
      $('#content').fadeTo( 'slow', 1 );
    }
  } );
}

Let’s look at each chunk of the above code:

        1. Init the form once the document is ready
          We use the jQuery object, $, to trigger our init() function once the DOM is ready.
        2. Hide the form, set the submit handler, and position the form
          The first thing we do inside the init() function itself is make some changes to our form, #contactForm.First we hide it from the page using the jQuery hide() method. Then we set its submit event handler to our submitForm() function (which we’ll write in a moment). This ensures that, when the user submits the form, submitForm() is called instead of the native browser form submission kicking in. Finally, we add the positioned CSS class to the form to reposition it in the centre of the browser window.
        3. Make the “Send us an email” links open the form
          Next we bind an anonymous event handler function to the “Send us an email” links’ click events. This function fades out the page content so it’s only just visible in the background; fades the contact form in; and sets the focus on the “Your Name” field, ready for the user to start filling in the form. Finally, the function returns false to prevent the links from being followed.
        4. When the “Cancel” button is clicked, close the form
          Now we bind another anonymous function to the “Cancel” button’s click event, so that the user can close the form by clicking the button. The function simply fades the form out, and fades the page content back in.
        5. When the “Escape” key is pressed, close the form
          Similarly we bind a function to the contact form’s keydown event, so that we can read any key the user presses when they’re viewing the form. In this function, we check if the user has pressed the “Escape” key (character code: 27). If they have then we close the form by fading it out, and fading the content in.

Step 6: Write the submitForm() function

Screenshot of form buttons

We’ve now set up our form so that, rather than being submitted in the usual fashion, it will trigger the submitForm() function when the user submits it. This function needs to do some validation and, if all is well, submit the form data to the PHP script via Ajax.

Here’s the function in full:

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// Submit the form via Ajax
function submitForm() {
  var contactForm = $(this);
  // Are all the fields filled in?
  if ( !$('#senderName').val() || !$('#senderEmail').val() || !$('#message').val() ) {
    // No; display a warning message and return to the form
    $('#incompleteMessage').fadeIn().delay(messageDelay).fadeOut();
    contactForm.fadeOut().delay(messageDelay).fadeIn();
  } else {
    // Yes; submit the form to the PHP script via Ajax
    $('#sendingMessage').fadeIn();
    contactForm.fadeOut();
    $.ajax( {
      url: contactForm.attr( 'action' ) + "?ajax=true",
      type: contactForm.attr( 'method' ),
      data: contactForm.serialize(),
      success: submitFinished
    } );
  }
  // Prevent the default form submission occurring
  return false;
}

Here’s how the function works:

        1. Store the contact form in a variable
          Since we’ll be using it a lot throughout the function, we start off by storing the contact form element in a contactForm variable. This element is available to our function as the this variable, since the function is the event handler for the element’s submit event. We wrap the element in a jQuery object to make it easier to work with.
        2. Check all the fields are filled in
          Now we check that each field’s value is not empty by using the jQuery val() method on each field.
        3. Display a warning if the form isn’t completed
          If 1 or more of the fields are empty, we fade out the form, then fade in the #incompleteMessage div, which contains the “Please complete all the fields…” message. We keep the message there for the time specified by the messageDelay variable, then fade it out again. Once it’s faded out, we fade the form back in so that the user can complete it.
        4. Submit the form if it is completed
          Now we get to the meat of the JavaScript. If the form is completed then we first fade out the form, and fade in the “Sending your message…” box. Now we call the jQuery ajax()method to submit the form via Ajax to the PHP script. We pass the following arguments to the method:

          url
          The URL to send the form to. We grab this from the form’s action attribute, and append an ajax=true parameter to the query string so that our PHP script knows the form was sent via Ajax, rather than via the usual method.
          type
          The type of request to make ("POST" or "GET"). We grab this from the form’s method attribute, which in this case is set to "POST".
          data
          The data to send with the request. For this, we call the jQuery serialize() method on the contact form object. This method takes all the field names and values in the form and encodes the data in a query string. We then pass this string to the ajax() method so it can send the data to the PHP script.
          success
          This is a callback function that will be called once the Ajax request has finished and the browser has received the response from the server. We set this to our submitFinished() function, which we’ll write in a moment.
        5. Prevent the default form submission occurring
          Finally, our event handler returns false to prevent the form being submitted in the usual way.

Step 7: Write the submitFinished() function

Screenshot of success message

The last function we need to write is submitFinished(), which is called once the Ajax response from the PHP script has been received by the browser. This function needs to check the response and display a success or error message as appropriate:

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// Handle the Ajax response
function submitFinished( response ) {
  response = $.trim( response );
  $('#sendingMessage').fadeOut();
  if ( response == "success" ) {
    // Form submitted successfully:
    // 1. Display the success message
    // 2. Clear the form fields
    // 3. Fade the content back in
    $('#successMessage').fadeIn().delay(messageDelay).fadeOut();
    $('#senderName').val( "" );
    $('#senderEmail').val( "" );
    $('#message').val( "" );
    $('#content').delay(messageDelay+500).fadeTo( 'slow', 1 );
  } else {
    // Form submission failed: Display the failure message,
    // then redisplay the form
    $('#failureMessage').fadeIn().delay(messageDelay).fadeOut();
    $('#contactForm').delay(messageDelay+500).fadeIn();
  }
}
</script>

The function works as follows:

        1. Get the response
          jQuery passes the response from the PHP script as an argument to the submitFinished() function. We take this string and pass it through the jQuery trim() method to remove any whitespace.
        2. Fade out the “sending” message
          Next we fade out the “Sending your message…” box by calling the jQuery fadeOut() method.
        3. If email was sent successfully, display a success message
          If the response variable holds the string "success", as returned by our PHP script, then we know that the email was successfully queued for delivery. So we fade in the success message, hold it for a couple of seconds, then fade it out. We also reset the form fields to empty values, in case the user wants to send another message. Finally, once the success message has faded out, we fade the page content back in.
        4. If there was a problem, display a failure message
          If the PHP script returned anything other than "success" then we know there was a problem with the submission, so we display the failure message stored in the #failureMessage div, then fade the form back in so that the user can correct any problems with the form.

And that’s the end of our JavaScript!

Summary

We’ve now built our slick Ajax contact form. Not only does it look good, but it’s easy to use, and the visitor can send an email without ever having to leave the page they are reading. Nice!

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