Ajax and javascript articles

How I Decide Which Open Source AJAX Library to Use (04/10/2012)
... I also want to be able to easily combine the library with other JavaScript libraries, so well-name-spaced functions and variables are a plus. Finally, I want a focused design, so I'm looking just for an AJAX library; I don't need a large JavaScript framework that takes weeks to learn. Multiple developers will be using it, so the less they have to learn, the better. During most of 2005, these requirementsand a bit of searchingwould have left me with a small list of libraries from which to choose. I could investigate them and find one that fit the rest of my Web development framework without too much hassle....

5 Benefits Obtained through Ruby on Rails Web Development (06/19/2011)
... These pages pop up as per the visitor's needs and service them accordingly. Ruby on rails web development facilitates the user with the feature of scalability and robustness. However ruby on rails development in pretty much slower compared to other technologies. This is real story of every interpretative technologies / languages. But ruby on rails technology possesses a number of benefits in the field of website development....

Integrating AJAX into a Framework (09/20/2010)
... Adding in AJAX pages next to your normal code lets you see the relation, but it makes it much harder to identify all of an application's AJAX-entry points. Either option can work well; the most important point is to use a consistent approach. RPC AJAX implementations have the hardest time integrating with a front controller. This difficulty occurs because most RPC implementations are focused on exporting classes to JavaScript and have their own mini-controller implementation, which maps incoming calls to these classes. Many also generate JavaScript, which should be added to the page using a JavaScript include, which again needs its own basic controller logic....

What Is Ajax (08/31/2010)
... The results may then be integrated seamlessly into the page being viewed, without that page needing to be refreshed or a new one loaded. In Ajax applications, such server requests are not necessarily synchronized with user actions such as clicking on buttons or links. A well-written Ajax application may already have asked of the server, and received, the data required by the userperhaps before the user even knew she wanted it. This is the meaning of the asynchronous part of the Ajax acronym. The parts of an Ajax application that happen "under the hood" of the user's browser, such as sending server queries and dealing with the returned data, are written in JavaScript, and XML is an increasingly popular means of coding and transferring formatted information used by Ajax to efficiently transfer data between server and client....

JavaScript as a Primary Development Language for AJAX applications (08/24/2010)
... However, with less-complex elements, such as AJAX communications or visual effects (such as fading an element out), they are less useful because you still have to write all the glue, and that's a large part of the overall code. As AJAX becomes more popular and libraries mature, more and more solutions will be created that will generate all the JavaScript for you, allowing you to handle all the details from your primary development language. JavaScript's greatest advantage is that it runs directly on the client, so it can react immediately to the user's actions. This interaction allows a JavaScript-driven Web application to offer a highly interactive user experience. The experience is interactive because tasks such as reordering a record no longer take an entire page reload....

Promises and Problems of Combining AJAX with Other New Technologies (08/17/2010)
... Flash also has a different look than the rest of the elements on an HTML page, which makes it hard to deliver a consistent feel and operation when using it for small elements within a bigger picture. The drawbacks of Flashpoor JavaScript integration and a different look and feelare not insurmountable, but they do lead many people to pick a complete Flash solution when they need to do anything complicated. This helps control complexity, but it leaves you fully tied to a single vendor and means that you have to use Flash remoting for your communications layer instead of AJAX. Adding Flash to your AJAX application gives you the ability to support many graphical tasks that would be impossible without it, but be prepared for a more complex design and debugging process. Scalable Vector Graphics (SVG) The new technologies in the browser world are not as widely deployed as Flash, and some, like Microsoft's Extensible Application Markup Language (XAML), have had only beta releases....

XMLHttpRequest Overview (08/14/2010)
... The security sandbox reduces these potential problems. In addition, it simplifies the programming model because the JavaScript code can implicitly trust any data it loads from XMLHttpRequest. It can trust the data because the new data is just as secure as the page that loaded the initial page. Despite the fact that XMLHttpRequest provides only a small API and just a handful of methods and properties, it has its differences between browsers. These differences are mainly in event handling and object instantiation (in IE, XMLHttpRequest is actually an ActiveX object), so they aren't hard to work around....

Goals of AJAX (08/03/2010)
... An example of real-time search is the Google Suggest application (www.google.com/webhp?complete=1&hl=en), which suggests possible search terms in a drop-down widget as you type your query; the widget would also indicate the number of results the search would return. Similar approaches can be used for any search application. The possibilities range from selecting a user on which to change permissions to picking a city to which to send a package....

JavaScript Lives in a Web Page (12/27/2008)
... The most dynamic elements in HTML, beside the link, are event-related attributes. For example, onClick is one of the event-related attributes of HTML. The HTML attribute launches a script when the user clicks on a portion of the page sensitive to a mouse-click action set up by the HTML. However, because HTML itself has no dynamic components, it relies on scripts written in JavaScript. An event-related attribute in HTML is like having a starter on a car with no engine—JavaScript is the engine....

JavaScript Literals (12/27/2008)
... With numbers other than decimal values or very large numbers, special requirements exist. Scientific Notations If you need scientific notations or are returned a value written in a scientific notation, you will be glad to know that they are written in standard format. For example, you might see the value 9.00210066295925e+21 on the screen after your script has calculated some really big numbers. The letter e is followed by a plus or minus sign and from one to three integers....

JavaScript Variables (12/27/2008)
... The following are typical examples: var item; var price= 33.44; var wholeThing= 86.45 + (20 *7); var name="Willie B. Goode"; var address "123 Elm Street"; var subTotal=sumItems var mixString= 11.86 + "Toy Cats"; var test = (alpha > beta) By taking each variable one at a time, you can see how the different data types discussed are placed into a variable: The first example demonstrates that you can declare a variable but not give it a value....

JavaScript Operators (12/27/2008)
... All negative numbers are assigned using a unary operator. For example, the following little script uses a unary operator to create a variable with a negative value: <html> <head> <script language="JavaScript"> var posNum=85; var negNum= -posNum; document.write(negNum); </script> </head> <body bgcolor="honeydew"> </body> </html> The return of the script is -85 because the minus (-) unary operator defined the variable negNum as the negation of the variable posNum. Other common unary operators include increment or decrement operators (++ and - -) seen in counter variables. Finally, ternary operators combine three expressions into one....

JavaScript Arrays (12/27/2008)
... However, an array element can be called forth in any order and used just like a variable. The data and data types that can be assigned to an array element are identical to the data and data types that you can assign to variables. You will also find that you can assign objects the same kinds of data. (Remember that an array is an object because it is composed for more than a single property.) Setting Up an Array Arrays are created using a constructor, just like other objects....

Loops in JavaScript (12/27/2008)
... A typical use for a loop is to examine characters in a string. The length of the string is used as the termination condition, and each character is based on its linear position in the string. <html> <head> <title>For Loop</title> <script language="JavaScript"> var found = "Email address is missing @ symbol."; var emailAd=prompt("Please enter your email address:",""); for (var counter=0; counter <= emailAd.length; counter++) { //The charAt(n) function looks at the character 'n' in the string var findAt=emailAd....

Types of operators in JavaScript (12/25/2008)
... The variable bolts is divided by the value of the variable lot, and the remainder (modulo) is assigned to the variable bolts. It would be the same as writing this: var bolts = bolts % lot; However, instead of taking two operations, one does the trick of assignment and operation. Comparison Operators Probably the area of most mistakes in JavaScript with operators is confusing (or just forgetting) the difference between assignment operators and comparison operators. Assignment operators equate a value with a variable, array element, or object property. Comparison operators generate a Boolean value....

Conditional Structures (11/30/2008)
... The following script contains a single condition that resolves as false so that the conditional statement is not executed. <html> <head> <title>False Condition</title> <script language="JavaScript"> var alpha="High"; var beta="Low"; var message="The condition is not met"; if(alpha > beta) { message="The condition is met"; } document.write(message); </script> </head> <body bgcolor="mediumspringgreen"> </body> </html> The expression found to be false is the condition that the variable alpha is greater than the variable beta. Because beta's value is Low and alpha's value is High, and because letters higher in the alphabet are resolved to be greater than letters lower in the alphabet, the false Boolean value prevented the script from executing the conditional statement. When the condition is changed to this: if(beta >alpha) { the condition is found to be true, and the value of the variable message is changed to "The condition is met," and that's what appears on the screen....

The ''with'' Statement (11/04/2008)
...formName,elementName.value A typical form could include several different elements, such a first name, last name, address, city, state, ZIP code, Social Security number, and all other kinds of property details. Using the with statement, you can specify the object name once and then follow it with all of the properties and their values in this format: with (object) { statements with properties only } The statements are typically property values. In the following simple example, the script uses a single with statement and then places the property values of the object in the statements within the with context: <html> <head> <title>with</title> <script language="JavaScript"> function showEm(){ with (document.customer) { var alpha=fname....

Operators Precedence (10/23/2008)
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Nested Loops, label and continue Statements (10/22/2008)
... When one loop resides inside another loop, it's called a nested loop. In JavaScript, labels are not statements, but rather identifiers. If you have ever programmed in Basic, in which line numbers or labels are used to reference a line of code, you know what labels are. They are places in the script where the program can branch if a statement tells it to do so. The format for a label is as follows: label: statements In some respects, labels can be used like comments to help you organize your scripts, but they also can be used in conjunction with continue to send the program to execute the labeled portion of the script....

Advantages and Disadvantages of AJAX Techniques ~ AJAX Without XMLHttpRequest (11/05/2006)
... Only XMLHttpRequest supports synchronous calls, so if they are necessary for your application, then using it as a fallback will not be possible. Advantages and Disadvantages of AJAX Techniques Technique Advantages Disadvantages XMLHttpRequest Can make requests to pages not set up for AJAX Can set/get all HTTP headers Can make HTTP requests using any type (GET, POST, PROPFIND, and so on) Supports full control over POST requests, allowing for any type of data encoding Requests ActiveX to be enabled in IE 5 and 6 Is only available in newer versions of Opera and Safari Has small implementation differences between browsers IFrame Can make POST and GET HTTP requests Supportes all modern browsers Supports asynchronous file uploads Prohibits synchronous requests Server pages must be designed to work with IFrame requests Has implementation differences between browsers Can leave extra entries in browser history (depends on browser and implementation) All request data is URL-encoded, increasing request size Cookies Supports the largest number of browsers Few implementation differences between browsers Prohibits no synchronous requests Doesn't work with large requests/results Requires server pages to be designed to work with cookie requests Requires polling on the client Can make only GET HTTP requests If you're using a fully wrapped XMLHttpRequest and you don't use synchronous calls, providing transparent fallback to your program should be possible. You need only to replace the final throwing of an exception in the example init method with the instantiation of your IFrame HTTP client. The main item to remember about using another approach instead of XMLHttpRequest is that it's not going to gain you huge leaps in compatibility. The major browsers already support XMLHttpRequest....