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Benx Shen

A re-introduction to JavaScript - MDC - 1 views

  • var name = o && o.getName();
  • var name = otherName || "default";
  • The first argument to apply() is the object that should be treated as 'this'.
  • ...9 more annotations...
  • apply() has a sister function named call, which again lets you set 'this' but takes an expanded argument list as opposed to an array.
  • Closures
  • A closure is the combination of a function and the scope object in which it was created. Closures let you save state - as such, they can often be used in place of objects.
  • An unfortunate side effect of closures is that they make it trivially easy to leak memory in Internet Explorer.
  • The above code sets up the element to turn red when it is clicked. It also creates a memory leak. Why? Because the reference to el is inadvertently caught in the closure created for the anonymous inner function. This creates a circular reference between a JavaScript object (the function) and a native object (el).
  • delete el;
  • var clickHandler = function() { this.style.backgroundColor = 'red'; } (function() { var el = document.getElementById('el'); el.onclick = clickHandler; })();
  • Surprisingly, one trick for breaking circular references introduced by a closure is to add another closure:
  • It's useful to start with an idea of the language's history. JavaScript was created in 1995 by Brendan Eich, an engineer at Netscape, and first released with Netscape 2 early in 1996. It was originally going to be called LiveScript, but was renamed in an ill-fated marketing decision to try to capitalise on the popularity of Sun Microsystem's Java language — despite the two having very little in common. This has been a source of confusion ever since.
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Benx Shen

Mastering CSS Coding: Getting Started « Smashing Magazine - 1 views

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    Chinese new year animals horoscope2016
    Happy Chinese new year 2016 messages & quotes
    Happy new year 2016 greetings for Chinese
    Chinese new year 2016 funny poems
涼鞋

Enterprise Java Community: Introduction to the Spring Framework 2.5 - 0 views

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    setDataAccessObject
Benx Shen

Javascript - Event order - 0 views

  • When you use event capturing | | ---------------| |----------------- | element1 | | | | -----------| |----------- | | |element2 \ / | | | ------------------------- | | Event CAPTURING | ----------------------------------- the event handler of element1 fires first, the event handler of element2 fires last. Event bubbling When you use event bubbling / \ ---------------| |----------------- | element1 | | | | -----------| |----------- | | |element2 | | | | | ------------------------- | | Event BUBBLING | ----------------------------------- the event handler of element2 fires first, the event handler of element1 fires last.
  • addEventListener() method explained on the Advanced models page. If its last argument is true the event handler is set for the capturing phase, if it is false the event handler is set for the bubbling phase.
  • In the Microsoft model you must set the event’s cancelBubble property to true. window.event.cancelBubble = true In the W3C model you must call the event’s stopPropagation() method. e.stopPropagation()
Benx Shen

Javascript Closures - 0 views

  • Closure A "closure" is an expression (typically a function) that can have free variables together with an environment that binds those variables (that "closes" the expression).
  • Example 2: Associating Functions with Object Instance Methods
Benx Shen

Top 10 CSS Tutorials - Cameron Olthuis - 0 views

Benx Shen

/* Position Is Everything */ - Modern browser bugs explained in detail! - 0 views

Benx Shen

Groovy - User Guide - 0 views

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