JavaScript 2.0-The Complete Reference, Second ... - freecodingtutorial

Table 14-11: Additional Properties of the HTMLOptionElement Object
Property Description
Text String holding the text found enclosed by the opening and closing
tags. This is often confused with value; since the text
enclosed by the tags is sent to the server, its value is not
specified.
value String holding the text of the value attribute, which will be sent to the
server if the option is selected at submission time.
Scripting Select Menus
The fact that form fields are scriptable means that you can affect the appearance or content of
one element in response to actions users perform on another. We‘ll see this technique several
times later in this chapter, but perhaps the most common application is with select menus.
Related select menus provide the ability to present a large number of options very quickly to the
user. The key to building such menus in JavaScript is understanding how to edit or even add
new s to a menu on the fly. The traditional way to do this in JavaScript is to use the
new operator on the Option() constructor, and then insert the resulting option into the menu.
The Option constructor syntax is
var newOption = new Option(optionText, optionvalue);
where optionText is a string holding the text enclosed by the opening and closing
tags and optionValue is a string specifying the element‘s value attribute.
Once created, Option objects can be inserted into the options[] collection for a select menu.
You can delete any unused entries by setting their values to null. The following simple example
provides two menus, one with a country and another with a list of cities. The city menu will
change dynamically when the user chooses a country.
Related Select Test