Professional JavaScript For Web Developers

Chapter 5
As mentioned previously, the feature string is comma-delimited and, therefore, must contain no space
before or after a comma or equal sign. For example, the following string is invalid:
window.open(“http://www.wrox.com/”, “wroxwindow”,
“height=150, width= 300, top=10, left= 10, resizable =yes”);
This string won’t work because of the spaces after the commas and other spaces around a couple of
equal signs. Just remove the spaces and it works fine:
window.open(“http://www.wrox.com/”, “wroxwindow”,
“height=150,width=300,top=10,left=10,resizable=yes”);
The window.open() method returns a window object as its function value that is also the window object
for the newly created window (or for the frame, if the name given is the name of an existing frame).
Using this object, it’s possible to manipulate the new window:
var oNewWin = window.open(“http://www.wrox.com/”, “wroxwindow”,
“height=150,width=300,top=10,left=10,resizable=yes”);
oNewWin.moveTo(100, 100);
oNewWin.resizeTo(200, 200);
Also using this object, it is possible to close the new window using the close() method:
oNewWin.close();
If there is code in the new window, it can close itself by using:
window.close();
This only works in the new window. If you try to call window.close() in the main browser window,
you get a message saying that a script is trying to close the window and asking if you actually want it to
close. The general rule to remember is this: Scripts can close any windows that they open, but no others.
A new window also has a reference to the window that opened it stored in the opener property. The
opener property exists only on the topmost window object of the new window, making it safer to use
top.opener to access it. Example:
var oNewWin = window.open(“http://www.wrox.com/”, “wroxwindow”,
“height=150,width=300,top=10,left=10,resizable=yes”);
alert(oNewWin.opener == window);
//outputs “true”
In this example, a new window is opened and then its opener property is tested against the window
object to prove that opener does indeed point to window (this alert displays “true”).
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