AJAX, an acronym for Asynchronous JavaScript and XML, is a group of technologies combines to accomplish powerful new forms of the web interactions. It’s composed of JavaScript, the XMLHTTPRequest object and XML, JSON, (X)HTML or even plain text.
Asynchronous means that you can make an HTTP request to a server and continue to process other data while waiting for the server’s response. For example, you can make requests to a server-side script to retrieve data from a database as XML, send data to a server-side script to be stored in a database or simple load a static XML file to populate pages of your web site without ever refreshing the page.
Behind the scenes data transfers are accomplished through the XMLHTTPRequest object, which is the heart of the AJAX engine, as it’s used to exchange data asynchronously with a server-side language, XML or other text format. It combines with the DOM (Document Object Model) to display the AJAX response data as (X)HTML and CSS.
The DOM is a language-independent interface that makes common web page elements accessible through scripting languages. This is extremely useful when working with dynamic data, such as an AJAX response, because it can be parsed by JavsScript and added to page elements on the fly without a browser refresh.
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I created a third ASP.NET online class called Database Web Development with ASP.NET at LVS Online.com.
This 6-week class will focus on how you can interact with databases such as SQL Server, MySQL and Microsoft Access using ASP.NET and C#. I start with the very basics on explaining how to use data source controls and objects in ADO.NET (Connection, Command, DataReader and DataSet) to retrieve, update and delete records in a database.
The great thing about ASP.NET is that you can work with almost any data source and are not limited to a Microsoft based technology. I provide a sample database in three separate versions (SQL Server, MySQL and Microsoft Access) and explain how SQL (Structure Query Language) statements are used to interact with your data.
The class is only $25 and there are no other materials or software needed.
Topics Covered:
Week 1: Database Overview (SQL Server, MySQL, Microsoft Access)
Week 2: Using SqlDataSource; SELECT statement and filtering data
Week 3: ADO.NET Review; Connection, Command and DataReader objects
Week 4: Updating and Inserting data (using data controls and ADO.NET objects)
Week 5: Databinding Techniques with GridView and DetailsView controls
Week 6: Understanding Stored Procedures (SQL Server and MySQL)
Extra: Concurrency issues and Transaction benefits
To give you an idea of how each lesson looks, here is the first lesson (.pdf).
Steve Souders is the author of High Performance Web Sites and the creator of YSlow, the Firebug extension gave a presentation at SXSW09 about how to speed up website performance.
Steve, now working at Google, discussed the next set of best practices he’s developed, including advanced techniques for loading JavaScript, where not to place inline scripts, and the importance of using multiple domains to improve web performance.
Here are his presentation notes (.pdf) as well.
I am teaching an online class to help students learn how to install, setup, monetize and customize a WordPress blog. This six week class will guide you step-by-step through all aspects of WordPress development.
This class is offered through this website only and I will email students a new lesson each week. Each lesson will be between 8-15 pages in length and have an assignment(s) that the student can work on if they desire.
Week 1 – Getting Started
- Blogging Basics
- Types of blogs
- Manual installation on a web server
Week 2 – Administration
- Understanding the Dashboard
- Setting up user accounts
- Elements of a Post
- Managing Posts, Categories and tags
- Adding an About page
- Adding your links
Week 3 – Site Design: Themes
- How to find and install new themes
- The basics components and files of a theme
- How to use widgets
- Quick PHP Overview
- Review of basics template tags
Week 4 – Adding Functionality
- What is a Plugin?
- How to find and install plugins
- Popular and useful plugins
Week 5 – Marketing
- Adding Analytics and RSS Feeds
- SEO Optimization
- Integrating social media sites
- How to monetize your blog
Week 6 – Themes: ‘Under the Hood’
- Blog design considerations
- Dissecting how a theme works
- Creating a basic theme from scratch
Class Requirements
The only requirement for the class is that you have a environment that includes Apache, PHP and MySQL. This can be obtained either by having a webhost webhost (I use GoDaddy) or using a prebuilt installation on your local Windows PC using WAMP Server or XAMPP.
Class Website
I have created a seperate website http://www.understandingwordpress.com for this class for which I will post additional material as well as answer students questions that can be viewed by everyone.
Sample Lesson
Here is the first lesson (.pdf) for you to look over and give you an idea of how topics will be covered.
Cost
The cost of the class will be $25 and will be payable to me via PayPal. Once I receive payment, within 48 hours (normally sooner), I will email you giving you details about the class and when the class will start.
Lorelle VanFossen is considered one of top experts on blogging and WordPress in the world and can be regularly seen keynoting at large blogger conferences such as WordCamp and SOBcon.
Lorelle was kind enough to give me some of her time to answer a few questions on blogging, analytics and the WordPress community.
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I created a beginner JavaScript class called JavaScript: The Basics at LVS Online.com.
This 6-week class will teach the students the basics of programming in general as well as the core concepts of using JavaScript. This will also prepare students to take my intermediate JavaScript class. JavaScript’s popularity is still on the rise and this is a great way to get some experience on programming and understand what cool things you can do with this language.
The class is only $25 and there are no other materials or software needed.
Topics Covered:
Week 1: Components of JavaScript and ECMAScript
Week 2: Data types, Arrays, and Conditional Statements: If..else, and switch
Week 3: Writing Loops, Functions and Understanding Variable Scope
Week 4: JavaScript Native Objects: Math, Date, Array and String
Week 5: Browser Objects (Location, Screen, Forms, Images) and DOM Overview
Week 6: Script Review and Common Troubleshooting
To give you an idea of how each lesson looks, here is the first lesson (.pdf).
Christian Heilmann is an author of books such as Beginning JavaScript with DOM Scripting and Ajax: From Novice to Professional and Web Development Solutions: Ajax, APIs, Libraries, and Hosted Services Made Easy, speaks all around world as an International Developer Evangelist for Yahoo!, and is an all around Web guru.
Christian was nice enough to give me some of his time to answer questions about the future of the web, accessibility, conferences and of course JavaScript.
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A while ago, I wrote a post on how to create a JavaScript Style Switcher, but recently I found the need to create a PHP based one. There are many ways to do this in PHP using sessions, arrays, cookies, etc. I created one that only takes a few lines of code and is super easy to implement.
This PHP Style Switcher can be done in two easy steps.
Step One: Setting styles
The first step is to create a new file on your server named switcher.php and paste the following code into it:
<?php
/* expire in 1 year */
setcookie("sitestyle", $_GET['set'], time()+31536000);
header("Location: $HTTP_REFERER");
?>When it’s queried, this file will write a cookie for the user detailing which site style to use. The cookie is set to expire in one year, and then the script sends the user back to the referring page. All of this happens behind the scenes, so the user will never really “see” switcher.php in action.
Telling switcher.php which site style to use is an equally simple matter. You can query it using conventional HREF links in text, images, or even flash
<a href="switcher.php?set=red">change to RED style!</a>
Step Two: Detecting styles
<link rel="stylesheet" type="text/css" media="screen"
title="User Defined Style"' href="<?php echo
(!$_COOKIE["sitestyle"])
?'default':$_COOKIE["sitestyle"]
?>.css" />
This tiny script detects which style is in the user’s cookies and prints out the result. If the user doesn’t have cookies enabled, or just hasn’t chosen a site style for themselves yet, the script will default to “default.css”.
So there you have it. A cross-browser, backwards-compatible, forwards-compatible, standards-compliant style sheet switcher in just five lines of code. It’s fast, straightforward, and universally accessible because there’s no processing done on the client side.
Here is the code (.zip) as well for you to review.
I created a second ASP.NET online class called Intermediate Web Development with ASP.NET at LVS Online.com.
This 6-week class will continue from my first ASP.NET class and focus more on ‘real-world’ ASP.NET programming topics. Since the first class focused on getting you up to speed on how ASP.NET works and the C# programming language, this intermediate class lets you take those skills in developing ASP.NET web sites.
The class is only $25 and there are no other materials or software needed.
Topics Covered:
Week 1: Master Page Basics
Week 2: Creating an ASP.NET Website from and HTML/CSS Design
Week 3: View State, Query String, Cookies, and Session State
Week 4: OOP: Building Your Own Objects
Week 5: Creating Your Own Controls: User Controls
Week 6: Error Handling
Extra: Website Navigation: Building a SiteMap
To give you an idea of how each lesson looks, here is the first lesson (.pdf).
