JavaScript Examples Bible - UserWorks Technologies

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HR.align
JavaScript Examples Bible: The Essential Companion to JavaScript Bible
invokes the same setHRAttr() function, passing a reference to itself so that the
function can inspect details of the element. Figure 5-1 shows the page after several
choices have modified the HR element.
Figure 5-1: Modifying HR element properties
The first task of the setHRAttr() function is to make sure that only browsers
capable of treating the HR element as an object get to the meat of the function. As
the page loads, the document.all property is set for NN6 using a normalization
technique described in Chapter 14 of the JavaScript Bible.
For suitably equipped browsers, the function next reads the string from the
value property of the SELECT object that is passed to the function. If a selection is
made (that is, other than the first, empty one), then the single, nested statement
uses the setAttribute() method to assign the value to the attribute whose name
matches the name of the SELECT element.
Listing 19-2: Controlling HR Object Properties
HR Object Properties
// document.all normalization trick for NN6
if (navigator.appName == “Netscape” && parseInt(navigator.appVersion) >= 5) {
document.all = document.getElementsByTagName(“*”)
}
// one function does all!
function setHRAttr(select) {