fundamentals of the jQuery library

1、why is jquery

• Only 32kB minified and gzipped. Can also be included as an AMD module
• Supports CSS3 selectors to find elements as well as in style property manipulation
• IE, Firefox, Safari, Opera, Chrome, and more

2、Downloading jQuery using Bower

jQuery is registered as a package with Bower. You can install the latest version of jQuery with the command:

bower install jquery

This will install jQuery to Bower's install directory, the default being bower_components. Within bower_components/jquery/dist/ you will find an uncompressed release, a compressed release, and a map file.

if you wish to install just the compressed jQuery 2.1.0, you can install just that file with the following command:

bower install http://code.jquery.com/jquery-2.1.4.min.js

3、Using jQuery with a CDN

CDNs can offer a performance benefit by hosting jQuery on servers spread across the globe. This also offers an advantage that if the visitor to your webpage has already downloaded a copy of jQuery from the same CDN, it won't have to be re-downloaded.

<script src="//code.jquery.com/jquery-1.11.3.min.js"></script>
<script src="//code.jquery.com/jquery-migrate-1.2.1.min.js"></script>

To see all available files and versions, visit http://code.jquery.com

4、References：

http://jquery.com/

https://github.com/jquery/jquery

http://plugins.jquery.com/

 

5、plugins with AMD

/*==============jquery插件queue.js，符合AMD规范============*/

define( [
    "./core",
    "./data/var/dataPriv",
    "./deferred",
    "./callbacks"
], function( jQuery, dataPriv ) {

jQuery.extend( {
    queue: function( elem, type, data ) {
        //...
    },

    dequeue: function( elem, type ) {
        //...
    },

    // Not public - generate a queueHooks object, or return the current one
    _queueHooks: function( elem, type ) {
        //...
    }
} );

jQuery.fn.extend( {
    queue: function( type, data ) {
        //...
    },
    dequeue: function( type ) {
        return this.each( function() {
            jQuery.dequeue( this, type );
        } );
    },
    clearQueue: function( type ) {
        return this.queue( type || "fx", [] );
    },

    // Get a promise resolved when queues of a certain type
    // are emptied (fx is the type by default)
    promise: function( type, obj ) {
        //...
    }
} );

return jQuery;
} );

/*=============core.js==================*/
define( [
    "./var/arr",
    "./var/document",
    "./var/slice",
    "./var/concat",
    "./var/push",
    "./var/indexOf",
    "./var/class2type",
    "./var/toString",
    "./var/hasOwn",
    "./var/support",
    "./core/DOMEval"
], function( arr, document, slice, concat,
    push, indexOf, class2type, toString, hasOwn, support, DOMEval ) {

var
    version = "@VERSION",

    // Define a local copy of jQuery
    jQuery = function( selector, context ) {

        // The jQuery object is actually just the init constructor 'enhanced'
        // Need init if jQuery is called (just allow error to be thrown if not included)
        return new jQuery.fn.init( selector, context );
    },

    // Support: Android<4.1
    // Make sure we trim BOM and NBSP
    rtrim = /^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g,

    // Matches dashed string for camelizing
    rmsPrefix = /^-ms-/,
    rdashAlpha = /-([a-z])/g,

    // Used by jQuery.camelCase as callback to replace()
    fcamelCase = function( all, letter ) {
        return letter.toUpperCase();
    };

jQuery.fn = jQuery.prototype = {

    // The current version of jQuery being used
    jquery: version,

    constructor: jQuery,

    // The default length of a jQuery object is 0
    length: ,
    // Execute a callback for every element in the matched set.
    each: function( callback ) {
        return jQuery.each( this, callback );
    },

    map: function( callback ) {
        return this.pushStack( jQuery.map( this, function( elem, i ) {
            return callback.call( elem, i, elem );
        } ) );
    }
};

jQuery.extend = jQuery.fn.extend = function() {
    //...
};

jQuery.extend( {

    // Unique for each copy of jQuery on the page
    expando: "jQuery" + ( version + Math.random() ).replace( /\D/g, "" ),

    // Assume jQuery is ready without the ready module
    isReady: true,

    error: function( msg ) {
        throw new Error( msg );
    }
} );

return jQuery;
} );