javascript

Chapter 8: The Browser Object Model
The end result is that there ’ s no way to determine the size of the browser window itself, but it is possible
to get the dimensions of the page viewport as shown in the following example:
var pageWidth = window.innerWidth,
pageHeight = window.innerHeight;
if (typeof pageWidth != “number”){
if (document.compatMode == “CSS1Compat”){
pageWidth = document.documentElement.clientWidth;
pageHeight = document.documentElement.clientHeight;
} else {
pageWidth = document.body.clientWidth;
pageHeight = document.body.clientHeight;
}
}
In this code, pageWidth and pageHeight are assigned initial values of window.innerWidth and window
.innerHeight , respectively. A check is then done to see if the value of pageWidth is a number; if not, then
the code determines if the page is in standards mode by using document.compatMode (this property is
discussed fully in Chapter 10 ). If it is, then document.documentElement.clientWidth and document
.documentElement.clientHeight are used; otherwise, document.body.clientWidth and
document.body.clientHeight are used.
The browser window can be resized using the resizeTo() and resizeBy() methods. Each method
accepts two arguments: resizeTo() expects a new width and height, and resizeBy() expects the
differences in each dimension. Here ’ s an example:
//resize to 100 x 100
window.resizeTo(100, 100);
//resize to 200 x 150
window.resizeBy(100, 50);
//resize to 300 x 300
window.resizeTo(300, 300);
As with the window - movement methods, the resize methods may be disabled by the browser and are
disabled by default on Opera and IE 7 and later. Also like the movement methods, these methods apply
only to the topmost window object.
Navigating and Opening Windows
The window.open() method can be used both to navigate to a particular URL and to open a new
browser window. This method accepts four arguments: the URL to load, the window target, a string of
features, and a Boolean value indicating that the new page should take the place of the currently loaded
page in the browser history. Typically only the first three arguments are used; the last argument applies
only when not opening a new window.
If the second argument passed to window.open() is the name of a window or frame that already exists,
then the URL is loaded into the window or frame with that name. Here ’ s an example:
//same as < a href=”http://www.wrox.com” target=”topFrame” > < /a >
window.open(“http://www.wrox.com/”, “topFrame”);
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