JavaScript Examples Bible - UserWorks Technologies

Chapter 4 ✦ The Document and Body Objects (Chapter 18)
Example
Use The Evaluator (Chapter 13 in the JavaScript Bible) to experiment with the
defaultCharset property. To see the default setting applied to the page, enter the
following statement into the top text box:
document.defaultCharset
documentElement
NN2 NN3 NN4 NN6 IE3/J1 IE3/J2 IE4 IE5 IE5.5
Compatibility ✓ ✓ ✓
Example
Use The Evaluator (Chapter 13 in the JavaScript Bible) to examine the behavior
of the documentElement property. In IE5+ or NN6, enter the following statement
into the top text field:
document.documentElement.tagName
The result is HTML, as expected.
expando
NN2 NN3 NN4 NN6 IE3/J1 IE3/J2 IE4 IE5 IE5.5
Compatibility ✓ ✓ ✓
Example
Use The Evaluator (Chapter 13 in the JavaScript Bible) to experiment with the
document.expando property in IE4+. Begin by proving that the document object
can normally accept custom properties. Type the following statement into the top
text field:
document.spooky = “Boo!”
This property is now set and stays that way until the page is either reloaded or
unloaded.
Now freeze the document object’s properties with the following statement:
document.expando = false
If you try to add a new property, such as the following, you receive an error:
document.happy = “tra la”
Interestingly, even though document.expando is turned off, the first custom property
is still accessible and modifiable.
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document.expando