Properties of the options array itself
The keyword here is "itself". In the last page, we looked at properties of elements of the options array, NOT the options array itself.
Just to refresh our minds, here are the properties we looked at last section:
We will now look at properties of the options array itself:
Using the above table, to use the properties, we would do the following:
Lets see this in action:
<form name="George"> <p><select name="example" size="1"> <option value="1">choice1</option> <option value="2">choice2</option> <option value="3">choice3</option> </select></p> </form>
Using the length property, we can see how many elements are in the selection list:
As you can see, it alerts "3", since there are three elements in the list.
The selectedIndex property informs the index number of the element selected, and updates itself whenever a new selection is made.
Make a selection:
The selectedIndex property updates itself if you change elements, so if you had selected "choice1", it alerts "0" (since array indexes start at 0), if you than changed and selected "choice2", it will alert "1" instead. The example above may not seem like much, but it paves the way for many useful scripts.