JavaScript Examples Bible - UserWorks Technologies

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JavaScript Examples Bible: The Essential Companion to JavaScript Bible
windowObject.scrollBy()
Example
To work with the scrollTo() method, you can use Listings 16-31 through 16-33
(the window.scroll() method) but substitute window.scrollTo() for window.
scroll(). The results should be the same. For scrollBy(), the example starts with
the frameset in Listing 16-34. It loads the same content document as the window.
scroll() example (Listing 16-32), but the control panel (Listing 16-35) provides
input to experiment with the scrollBy() method.
Listing 16-34: Frameset for ScrollBy Controller
window.scrollBy() Method
Notice in Listing 16-35 that all references to window properties and methods are
directed to the display frame. String values retrieved from text fields are converted
to number with the parseInt() global function.
Listing 16-35: ScrollBy Controller
ScrollBy Controller
function page(direction) {
var pixFrame = parent.display
var deltaY = (pixFrame.innerHeight) ? pixFrame.innerHeight :
pixFrame.document.body.scrollHeight
if (direction == “up”) {
deltaY = -deltaY
}
parent.display.scrollBy(0, deltaY)
}
function customScroll(form) {
parent.display.scrollBy(parseInt(form.x.value), parseInt(form.y.value))
}
ScrollBy Controller
Enter an Horizontal increment