Note : The Options Collection is supported by both Netscape and Internet Explorer.
The Options collection is an ordered, indexed array, containing a reference to every <OPTION>
element in a given <SELECT>
element. A separate options collection is available for each different <SELECT>
element in the document and the options collection can only be referenced through a reference to a valid <SELECT>
element object.
Option Objects would normally be retrieved by their index in the options collection. I.e.:
document.<SELECT>reference.options(1).value
returns the VALUE
attribute of the second <OPTION>
element in the <SELECT>
element referenced by <SELECT>
reference. For example, consider the following:
<SELECT NAME="Songs">
<OPTION VALUE="BuryLove" ID="BLove">Bury Your Love Like Treasure
<OPTION VALUE="JacketHangs" ID="JHangs">Jacket Hangs
<OPTION VALUE="LoverAndConfidante" ID="Lover">Lover And Confidante
<SELECT>
Calling the following in a script function:
document.Songs.options(1).value
would return JacketHangs
.
A string value can be used however, as long as that string is a valid identifier (ID
attribute value) for an <OPTION>
element in the referenced <SELECT>
element in the document.
E.g.
document.Songs.options('Lover').text
would return the Lover And Confidante
- the displayed text for the <OPTION>
element whose ID
attribute is 'Lover'.
length
The length
property returns the number of options in the collection. Note that the length
count starts at 1, not 0 as the options collection index does. Therefore, the length
property may return a value of 5, but to access the 3rd option in a <SELECT>
, you'd need to use document.<SELECT>reference.options(2).property
add
The add
method can be used to add option objects to the collection. Note that the new <OPTION>
element must first be created by using the createElement
method of the Document Object.
The add
method takes the single argument of index
which specifies where in the options collection the new element is to be placed. If no index
argument is specified, the new option object is appended to the end of the collection.
item
The item
method retrieves single items, or sub-collections from an areas collection. It accepts the following arguments:
options.item(index, sub-index)
If index
is a number, then the method returns a reference to the <OPTION>
at that position in the options collections index. I.e.
strTag=document.<SELECT>reference.options.item(2).value
would make strTag
be the value of the VALUE
attribute of the <SELECT>
's third <OPTION>
. As you can see, this is effectively the long-hand version of using document.<SELECT>reference.options(2).property
.
If the index
property is a string value, then the item
method returns a sub-collection, containing a reference to every option object in the select object that has its NAME
or ID
attribute set to the string contained in the index
argument. To retrieve certain element objects from this sub-collection, the sub-index
argument must be used.
remove
The remove
method can be used to remove an option object from a select object. For example, using the <SELECT>
/<OPTION>
set from above, using:
document.Songs.options.remove(1)
would remove the second <OPTION>
choice, compressing the options collection. Note that removal of option objects can also be achieved by setting their value
property to "" (i.e. null).
© 1995-1998, Stephen Le Hunte
file: /Techref/language/html/ib/Scripting_Reference/optcol.htm, 5KB, , updated: 2004/3/1 16:47, local time: 2024/8/14 17:53,
3.145.186.67:LOG IN
|
©2024 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions? <A HREF="http://ecomorder.com/techref/language/html/ib/Scripting_Reference/optcol.htm"> The Options collection</A> |
Did you find what you needed? |
Welcome to ecomorder.com! |
Ashley Roll has put together a really nice little unit here. Leave off the MAX232 and keep these handy for the few times you need true RS232! |
.