Using prototype.js v1.4.0

Using prototype.js v1.4.0

Using the $() function

The $() function is a handy shortcut to the all-too-frequent document.getElementById() function of the DOM. Like the DOM function, this one returns the element that has the id passed as an argument.

Unlike the DOM function, though, this one goes further. You can pass more than one id and $() will return an Array object with all the requested elements. The example below should illustrate this.

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Using the $A() function

The $A() function converts the single argument it receives into an Array object.

This function, combined with the extensions for the Array class, makes it easier to convert or copy any enumerable list into an Array object. One suggested use is to convert DOM NodeLists into regular arrays, which can be traversed more efficiently. See example below.

 Buchanan, Steven Callahan, Laura Davolio, Nancy


   

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Using the $H() function

The $H() function converts objects into enumerable Hash objects that resemble associative arrays.

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Using the $R() function

The $R() function is simply a short hand to writing new ObjectRange(lowerBound, upperBound, excludeBounds).

Jump to the ObjectRange class documentation for a complete explanation of this class. In the meantime, let's take a look at a simple example that also shows the usage of iterators through the each method. More on that method will be found in the Enumerable object documentation.

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Using the Try.these() function

The Try.these() function makes it easy when you want to, ahem, try different function calls until one of them works. It takes a number of functions as arguments and calls them one by one, in sequence, until one of them works, returning the result of that successful function call.

In the example below, the function xmlNode.text works in some browsers, and xmlNode.textContent works in the other browsers. Using the Try.these() function we can return the one that works.

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