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Javascript Tuts and Info

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Introduction to jQuery tools. Essential tools for modern websites Let's face it: do you really need drag-and-drop, resizable windows or sortable lists in your web applications? Websites are not desktop applications. They are different. What you really need is high usability, striking visual effects and all those "web 2.0" goodies that you have seen on your favourite websites. This library is an answer to this need. All tools can be used together, extended, configured and styled.

You'll find your personal way of using the library. Small size. The UI part of this library weighs 4.45 Kb. You can pick your own selection of tools from the download page or you can load the most common combinations directly from a free Content Delivery Network (CDN). The CDN is configured with the proper expire headers and compression settings so that the file loads fast. For beginners A large demo area lets you copy & paste working code directly into your pages.

For serious programmers Understandable API design. Understanding jQuery Tools. Classical Inheritance in JavaScript. Douglas Crockford www.crockford.com And you think you're so clever and classless and free — John Lennon JavaScript is a class-free, object-oriented language, and as such, it uses prototypal inheritance instead of classical inheritance. This can be puzzling to programmers trained in conventional object-oriented languages like C++ and Java.

But first, why do we care about inheritance at all? The second reason is code reuse. To demonstrate this, we will introduce a little sugar which will let us write in a style that resembles a conventional classical language. Classical Inheritance First, we will make a Parenizor class that will have set and get methods for its value, and a toString method that will wrap the value in parens. The syntax is a little unusual, but it is easy to recognize the classical pattern in it. So now we can write myParenizor = new Parenizor(0); myString = myParenizor.toString(); As you would expect, myString is "(0)". The inherits method is similar to Java's extends. Sugar. Oop - What's the best way to define a class in JavaScript. Inheritance and the prototype chain - JavaScript. JavaScript is a bit confusing for developers experienced in class-based languages (like Java or C++), as it is dynamic and does not provide a class implementation (although the keyword class is a reserved keyword and cannot be used as a variable name).

When it comes to inheritance, JavaScript only has one construct: objects. Each object has an internal link to another object called its prototype. That prototype object has a prototype of its own, and so on until an object is reached with null as its prototype. null, by definition, has no prototype, and acts as the final link in this prototype chain. While this is often considered to be one of JavaScript's weaknesses, the prototypal inheritance model is in fact more powerful than the classic model. It is, for example, fairly trivial to build a classic model on top of a prototypal model, while the other way around is a far more difficult task.

Inheritance with the prototype chain Inheriting properties In this example, someObject. Performance. 3 ways to define a JavaScript class. Introduction JavaScript is a very flexible object-oriented language when it comes to syntax. In this article you can find three ways of defining and instantiating an object. Even if you have already picked your favorite way of doing it, it helps to know some alternatives in order to read other people's code.

It's important to note that there are no classes in JavaScript. Functions can be used to somewhat simulate classes, but in general JavaScript is a class-less language. 1. This is probably one of the most common ways. Function Apple (type) { this.type = type; this.color = "red"; this.getInfo = getAppleInfo; } function getAppleInfo() { return this.color + ' ' + this.type + ' apple'; } To instantiate an object using the Apple constructor function, set some properties and call methods you can do the following: var apple = new Apple('macintosh'); apple.color = "reddish"; alert(apple.getInfo()); 1.1. 1.2. Again, you can use the new objects exactly the same way as in 1. and 1.1. 2. 3. Summary. Object-Oriented Programming with JavaScript, Part I: Inheritance: Inheritance through Functions - Doc JavaScript - Webreference.com.

Object-Oriented Programming with JavaScript, Part I: Inheritance Inheritance through Functions Although JavaScript does not support an explicit inheritance operator, you can implement inheritance in other ways. There are two different ways to establish a hierarchy of classes in JavaScript. The first method to create an object as a subclass of another object, is to call the superclass constructor function inside the subclass object definition. Let's look at the following example: function superClass() { this.bye = superBye; this.hello = superHello; } function subClass() { this.inheritFrom = superClass; this.inheritFrom(); this.bye = subBye; } function superHello() { return "Hello from superClass"; } function superBye() { return "Bye from superClass"; } function subBye() { return "Bye from subClass"; } function printSub() { var newClass = new subClass(); alert(newClass.bye()); alert(newClass.hello()); } Convince yourself that it is working correctly.

Let's take another example. Eloquent JavaScript: A Modern Introduction to Programming.