Alphabetical Object Reference (Dynamic HTML: The Definitive Reference, 2nd Edition)

a	`NN 6 IE 4 DOM 1`

The a object reflects the a element, regardless of whether the element is set up to be an anchor, link, or both. Early versions of Navigator and Internet Explorer treat this object only as a member of the links[] and/or anchors[ ] arrays of a document. Starting with IE 4 and Netscape 6, you can access the object through supported element object reference syntax (e.g., the document.all[] collection for IE or document.getElementById( ) for IE 5 and later and Netscape 6).

HTML Equivalent

<a>

Object Model Reference

[window.]document.links[i]
[window.]document.anchors[i]
[window.]document.getElementById("elementID")

Object-Specific Properties

`charset`	`coords`	`dataFld`	`dataFormatAs`	`dataSrc`	`hash`
`host`	`hostname`	`href`	`hreflang`	`Methods`	`mimeType`
`name`	`nameProp`	`pathname`	`port`	`protocol`	`protocolLong`
`rev`	`search`	`shape`	`target`	`text`	`type`
`urn`

Object-Specific Methods

None.

Object-Specific Event Handler Properties

Handler	NN	IE	DOM
`onblur`	n/a	4	n/a
`onclick`	2	3	2
`ondblclick`	4	4	n/a
`onfocus`	n/a	4	n/a
`onhelp`	n/a	4	n/a
`onmousedown`	4	4	2
`onmousemove`	6	4	2
`onmouseout`	3	4	2
`onmouseover`	2	3	2
`onmouseup`	4	4	2

Anchor-only a objects have no event handlers in Navigator through Version 4.

charset NN 6 IE 6 DOM 1
Read/Write
Character encoding of the document's content.

Example

if (document.getElementById("myAnchor").charset == "csISO5427Cyrillic") { // process for Cyrillic charset }

Value

Case-insensitive alias from the character set registry (ftp://ftp.isi.edu/in-notes/iana/assignments/character-sets).

Default

Determined by browser.

coords NN 6 IE 6 DOM 1
Read/Write
Defines the outline of an area to be associated with a particular link or scripted action. This property is a member of the a object, but really belongs to the area object, which inherits the properties of the a object. Coordinate values are entered as a comma-delimited list. If hotspots of two areas should overlap, the area that is defined earlier in the code takes precedence.

Example

document.getElementById("mapArea2").coords = "25, 5, 50, 70";

Value

Each coordinate is a length value, but the number of coordinates and their order depend on the shape specified by the shape attribute, which may optionally be associated with the element. For shape="rect", there are four coordinates (left, top, right, bottom); for shape="circle" there are three coordinates (center-x, center-y, radius); for shape="poly" there are two coordinate values for each point that defines the shape of the polygon.

Default

None.

dataFld NN n/a IE 4 DOM n/a
Read/Write
Used with IE data binding to associate a remote data source column value in lieu of an href attribute for a link. The datasrc attribute must also be set for the element. Setting both the dataFld and dataSrc properties to empty strings breaks the binding between element and data source. Works only with text file data sources in IE 5/Mac.

Example

document.getElementById("hotlink").dataFld = "linkURL";

Value

Case-sensitive identifier of the data source column.

Default

None.

dataFormatAs NN n/a IE 4 DOM n/a
Read/Write
Used with IE data binding, this property advises the browser whether the source material arriving from the data source is to be treated as plain text or as tagged HTML.

Example

document.getElementById("hotlink").dataFormatAs = "HTML";

Value

IE recognizes two possible settings: text | html.

Default

text

dataSrc NN n/a IE 4 DOM n/a
Read/Write
Used with IE data binding to specify the ID of the page's object element that loads the data source object for remote data access. Content from the data source to be inserted into the a element text is specified via the datafld property. Setting both the dataFld and dataSrc properties to empty strings breaks the binding between element and data source. Works only with text file data sources in IE 5/Mac.

Example

document.all.hotlink.dataSrc = "#DBSRC3";

Value

Case-sensitive identifier of the data source.

Default

None.

hash NN 2 IE 3 DOM 1
Read/Write
Provides that portion of the href attribute's URL following the # symbol, referring to an anchor location in a document. Do not include the # symbol when setting the property.

Example

document.getElementById("myLink").hash = "section3"; document.links[2].hash = "section3";

Value

String.

Default

None.

host NN 2 IE 3 DOM 1
Read/Write
This is the combination of the hostname and port (if any) of the server of the destination document for the link. If the port is explicitly part of the URL, the hostname and port are separated by a colon, just as they are in the URL. If the port number is not specified in an HTTP URL for IE, it automatically returns the default, port 80.

Example

document.getElementById("myLink").host = "www.megacorp.com:80"; document.links[2].host = "www.megacorp.com:80";

Value

String of hostname optionally followed by a colon and port number.

Default

Depends on server.

hostname NN 2 IE 3 DOM 1
Read/Write
This is the hostname of the server (i.e., a "two-dot" address consisting of server name and domain) of the destination document for the link. The hostname property does not include the port number.

Example

document.getElementById("myLink").hostname = "www.megacorp.com"; document.links[2].hostname = "www.megacorp.com";

Value

String of hostname (server and domain).

Default

Depends on server.

href NN 2 IE 3 DOM 1
Read/Write
Provides the URL specified by the element's href attribute.

Example

document.getElementById("myLink").href = "http://www.megacorp.com"; document.links[2].href = "http://www.megacorp.com";

Value

String of complete or relative URL.

Default

None.

hreflang NN 6 IE 6 DOM 1
Read/Write
Provides the language code of the content at the destination of a link. Requires that the href attribute or property also be set.

Example

document.getElementById("myLink").hreflang = "DE";

Value

Case-insensitive language code.

Default

None.

Methods NN n/a IE 4 DOM n/a
Read/Write
Provides an advisory attribute about the functionality of the destination of a link. A browser could use this information to display special colors or images for the element content based on what the destination does for the user, but Internet Explorer does not appear to do anything with this information.

Example

document.links[1].Methods = "post";

Value

Any valid HTTP method as a string.

Default

None.

mimeType NN n/a IE 4 DOM n/a
Read-only
Returns a plain-language version of the MIME type of the destination document at the other end of the link specified by the href attribute. You could use this information to set the cursor type during a mouse rollover. Don't confuse this property with the navigator.mimeTypes[] array and individual mimeType objects that Netscape Navigator refers to. This is not available in IE 4/Macintosh.

Example

if (document.getElementById("myLink").mimeType == "GIF Image") { ... }

Value

A plain-language reference to the MIME type as a string.

Default

None.

name NN 2 IE 3 DOM 1
Read/Write
This is the identifier associated with an element that turns it into an anchor. You can also use the name as part of the object reference.

Example

if (document.links[12].name == "section3") { ... }

Value

Case-sensitive identifier that follows the rules of identifier naming: it may contain no whitespace, cannot begin with a numeral, and should avoid punctuation except for the underscore character.

Default

None.

nameProp NN n/a IE 4 DOM n/a
Read-only
Returns just the filename, rather than the full URL, of the href attribute set for the element. Not available in IE 4/Macintosh.

Example

if (document.getElementById("myLink").nameProp == "logo2.gif") { ... }

Value

String.

Default

None.

pathname NN 2 IE 3 DOM 1
Read/Write
Provides the pathname component of the URL assigned to the element's href attribute. This consists of all URL information following the last character of the domain name, including the initial forward slash symbol.

Example

document.getElementById("myLink").pathname = "/images/logoHiRes.gif"; document.links[2].pathname = "/images/logoHiRes.gif";

Value

String.

Default

None.

port NN 2 IE 3 DOM 1
Read/Write
Provides the port component of the URL assigned to the element's href attribute. This consists of all URL information following the colon after the last character of the domain name. The colon is not part of the port property value.

Example

document.getElementById("myLink").port = "80"; document.links[2].port = "80";

Value

String (a numeric value as string).

Default

None.

protocol NN 2 IE 3 DOM 1
Read/Write
Indicates the protocol component of the URL assigned to the element's href attribute. This consists of all URL information up to and including the first colon of a URL. Typical values are: "http:", "file:", "ftp:", and "mailto:".

Example

document.getElementById("secureLink").protocol = "https:";

Value

String.

Default

None.

protocolLong NN n/a IE 4 DOM n/a
Read-only
Provides a verbose description of the protocol implied by the URL of the href attribute or href property. Not supported in IE 4/Macintosh, and appears to be deprecated .

Example

if (document.getElementById("myLink").protocolLong == "HyperText Transfer Protocol") { // statements for treating document as server file }

Value

String.

Default

None

rel NN 6 IE 4 DOM 1
Read/Write
Defines the relationship between the current element and the destination of the link. Also known as a forward link, not to be confused in any way with the destination document whose address is defined by the href attribute. Mainstream browsers do not take advantage of this attribute for the a element, but you can treat the attribute as a kind of parameter to be checked and/or modified under script control. See the discussion of the a element's rel attribute in Chapter 8 for a glimpse of how this property may be used in the future.

Value

Case-insensitive, space-delimited list of HTML 4.0 standard link types (as a single string) applicable to the element. Sanctioned link types are:

alternate

appendix

bookmark

chapter

contents

copyright

glossary

help

index

next

prev

section

start

stylesheet

subsection

Default

None.

rev NN n/a IE 4 DOM 1
Read/Write
Defines the relationship between the current element and the destination of the link. Also known as a reverse link. This property is not exploited yet in mainstream browsers, but you can treat the attribute as a kind of parameter to be checked and/or modified under script control. See the discussion of the a element's rev attribute in Chapter 8 for a glimpse of how this property may be used in the future.

Value

Case-insensitive, space-delimited list of HTML 4.0 standard link types (as a single string) applicable to the element. See the rel property for sanctioned link types.

Default

None.

search NN 2 IE 3 DOM 1
Read/Write
Provides the URL-encoded portion of a URL assigned to the href attribute that begins with the ? symbol. A document that is served up as the result of the search also may have the search portion available as part of the window.location property. You can modify this property with a script. Doing so sends the URL and search criteria to the server. You must know the format of data (usually name/value pairs) expected by the server to perform this properly.

Example

document.getElementById("searchLink").search="?p=Tony+Blair&d=y&g=0&s=a&w=s&m=25"; document.links[1].search="?p=Tony+Blair&d=y&g=0&s=a&w=s&m=25";

Value

String starting with the ? symbol.

Default

None.

shape NN 6 IE 6 DOM 1
Read/Write
Indicates the shape of a server-side image map area, with coordinates that are specified with the COORDS attribute. Intended for use by the area object, which inherits the properties of the a object.

Example

document.getElementById("myLink").shape = "circle";

Value

Case-insensitive shape constant as string: default | rect | rectangle | circle | poly | polygon.

Default

rect

target NN 2 IE 3 DOM 1
Read/Write
Provides the name of the window or frame that is to receive content as the result of navigating to a link. Such names are assigned to frames by the frame element's name attribute; for subwindows, the name is assigned via the second parameter of the window.open( ) method. If you need the services of a target attribute to open a linked page in a blank browser window and you also need the HTML to validate under strict HTML or XHTML DTDs (see Chapter 1), you can omit the target attribute in the code, but you must assign a value to the a element's target property by script after the page loads.

Example
document.getElementById("homeLink").target = "_top";
document.links[3].target = "_top";
Value

String value of the window or frame name, or any of the following constants (as a string): _parent | _self | _top | _blank. The _parent value targets the frameset to which the current document belongs; the _self value targets the current window; the _top value targets the main browser window, thereby eliminating all frames; and the _blank value creates a new window of default size.

Default

None.

text NN 4 IE n/a DOM n/a
Read-only
Returns the text between the a element's start and end tags. This property pre-dates the W3C DOM and should be used only if needed for Navigator 4.

Value

String value.

Default

None.

type NN 6 IE 6 DOM 1
Read/Write
This is the MIME type of the destination document at the other end of the link specified by the href attribute. A browser might use this information to assist in preparing support for a resource requiring a multimedia player or plugin.

Example

if (document.getElementById("myLink").type == "image/jpeg") { ... }

Value

Case-insensitive MIME type. A catalog of registered MIME types is available from ftp://ftp.isi.edu/in-notes/iana/assignments/media-types/.

Default

None.

urn NN n/a IE 4 DOM n/a
Read/Write
Indicates a Uniform Resource Name (URN) version of the destination document specified in the href attribute. This attribute is intended to offer support in the future for the URN format of URI, an evolving recommendation under discussion at the IETF (see RFC 2141). Although supported in IE, this attribute does not take the place of the href attribute.

Example

document.getElementById("link3").urn = "http://www.megacorp.com";

Value

Complete or relative URN as a string.

Default

None.

acronym, cite, code, dfn, em, kbd, samp, strong, var NN 6 IE 4 DOM 1

All these objects reflect the corresponding HTML phrase elements of the same name. Each of these phrase elements provides a context for an inline sequence of content. Some of these elements are rendered in ways to distinguish themselves from running text. See the HTML element descriptions in Chapter 8 for details. From a scripted standpoint, all phrase element objects share the same set of properties, methods, and event handlers.

HTML Equivalent

<acronym>
<cite>
<code>
<dfn>
<em>
<kbd>
<samp>
<strong>
<var>

Object Model Reference

[window.]document.getElementById("elementID")

Object-Specific Properties

None.

Object-Specific Methods

None.

Object-Specific Event Handler Properties

None.

all NN n/a IE 4 DOM n/a

A collection of elements nested within the current element. A reference to document.all, for example, returns a collection (array) of all element objects contained by the document, including elements that may be deeply nested inside the document's first level of elements. The collection is sorted in source code order of the element tags. You can retrieve a reference to an element with its ID by any of the following syntaxes:

document.all.elementID
document.all["elementID"]
document.all("elementID"]
document.all.item("elementID")
document.all.namedItem("elementID")

The W3C DOM equivalent (the document.getElementById( ) method) operates only from the document object, providing global reach to elements throughout the entire document.

Object Model Reference

elementReference.all

Object-Specific Properties

length

Object-Specific Methods

item( )

namedItem( )

tags( )

urns( )

Object-Specific Event Handler Properties

None.

length NN n/a IE 4 DOM n/a
Read-only
Returns the number of elements in the collection.

Example

var howMany = document.all.length;

Value

Integer.

item( ) NN n/a IE 4 DOM n/a
item(index[, subindex])
Returns a single object or collection of objects corresponding to the element matching the index value (or, optionally, the index and subindex values).

Returned Value

One object or collection (array) of objects. If there are no matches to the parameters, the returned value is null.

Parameters

index

When the parameter is a zero-based integer, the returned value is a single element corresponding to the specified item in source code order (nested within the current element); when the parameter is a string, the returned value is a collection of elements whose id or name properties match that string.

subindex

If you specify a string value for the first parameter, you can use the second parameter to specify a zero-based index that retrieves the specified element from the collection whose id or name properties match the first parameter's string value.

namedItem( ) NN n/a IE 6 DOM n/a
namedItem(IDOrName)
Returns a single object or collection of objects corresponding to the element matching the parameter string value.

Returned Value

One object or collection (array) of objects. If there are no matches to the parameters, the returned value is null.

Parameters

IDOrName

The string that contains the same value and case as the desired element's id or name attribute.

tags( ) NN n/a IE 4 DOM n/a
tags(tagName)
Returns a collection of objects (among all objects nested within the current element) whose tags match the tagName parameter.

Returned Value

A collection (array) of objects. If there are no matches to the parameters, the returned value is an array of zero length.

Parameters

tagName

A case-insensitive string that contains the element tag name only (no angle brackets), as in document.all.tags("p").

urns( ) NN n/a IE 5(Win) DOM n/a
urns(URN)
Returns a collection of nested element objects that have behaviors attached to them and whose URNs match the URN parameter.

Returned Value

A collection (array) of objects. If there are no matches to the parameters, the returned value is an array of zero length.

Parameters

URN

A string with a local or external behavior file URN.

anchors NN 2 IE 3 DOM 1

A collection of all a elements with assigned name attributes that make them behave as anchors (instead of links). Collection members are sorted in source code order. Navigator and Internet Explorer let you use array notation to access a single anchor in the collection (e.g., document.anchors[0], document.anchors["section3"]). Internet Explorer 4 also allows the index value to be placed inside parentheses instead of brackets (e.g., document.anchors(0)). If you want to use the anchor's name as an index value (always as a string identifier), be sure to use the value of the name attribute, rather than the id attribute. To use the id attribute in a reference to an anchor, access the object via a document.all.elementID (in IE only) or document.getElementById("elementID") reference.

Object Model Reference

document.anchors

Object-Specific Properties

length

Object-Specific Methods

item( )

namedItem( )

tags( )

urns( )

Object-Specific Event Handler Properties

None.

length NN 2 IE 3 DOM 1
Read-only
Returns the number of elements in the collection.

Example

var howMany = document.anchors.length;

Value

Integer.

item( ) NN 6 IE 4 DOM 1
item(index[, subindex]) item(index)
Returns a single anchor object or collection of anchor objects corresponding to the element matching the index value (or, optionally in IE, the index and subindex values).

Returned Value

One anchor object or collection (array) of anchor objects. If there are no matches to the parameters, the returned value is null.

Parameters

index

When the parameter is a zero-based integer (required in Netscape 6), the returned value is a single element that corresponds to the specified item in source code order (nested within the current element). When the parameter is a string, the returned value is a collection of elements whose id or name properties match that string.

subindex

In IE only, if you specify a string value for the first parameter (IE only), you can use the second parameter to specify a zero-based index that retrieves the specified element from the collection with id or name properties that match the first parameter's string value.

namedItem( ) NN 6 IE 6 DOM 1
namedItem(IDOrName)
Returns a single anchor object or collection of anchor objects corresponding to the element matching the parameter string value.

Returned Value

One anchor object or collection (array) of anchor objects. If there are no matches to the parameters, the returned value is null.

Parameters

IDOrName

The string that contains the same value as the desired element's id or name attribute.

tags( ) NN n/a IE 4 DOM n/a
tags(tagName)
Returns a collection of objects (among all objects nested within the current collection) with tags that match the tagName parameter. Implemented in all IE collections (see the all.tags( ) method), but redundant for collections of the same element type.

urns( ) NN n/a IE 5(Win) DOM n/a
urns(URN)
See the all.urns( ) method.

applet NN 3 IE 4 DOM 1

The applet object reflects the applet element.

HTML Equivalent

<applet>

Object Model Reference

[window.]document.appletName
[window.]document.getElementById("elementID")

Object-Specific Properties

`align`	`alt`	`altHTML`	`archive`	`code`
`codeBase`	`dataFld`	`dataSrc`	`height`	`hspace`
`name`	`object`	`src`	`vspace`	`width`

Object-Specific Methods

None.

Object-Specific Event Handler Properties

None.

align NN 6 IE 4 DOM 1
Read/Write
Defines the alignment of the element within its surrounding container. Only partially implemented in Netscape 6.2. See Section 8.1.5 at the beginning of Chapter 8 for the various meanings that different values bring to this property.

Example
document.getElementById("myApplet").align = "center";
Value

Any of the alignment constants: absbottom | absmiddle | baseline | bottom | left | middle | right | texttop | top.

Default

left

alt NN 6 IE 6 DOM 1
Read/Write
This is the text message to be displayed if the object or applet fails to load. There is little indication that setting this property on an existing applet object has any visual effect.

Example

document.myApplet.alt= "Image Editor Applet";

Value

Any quoted string of characters, but HTML tags are not interpreted.

Default

None.

altHTML NN n/a IE 4 DOM n/a
Read/Write
Provides the HTML content to be displayed if the object or applet fails to load. This can be a message, static image, or any other HTML that best fits the scenario. There is little indication that setting this property on an existing applet object has any visual effect.

Example

document.myApplet.altHTML = "<img src='appletAlt.gif'>";

Value

Any quoted string of characters, including HTML tags.

Default

None.

archive NN 6 IE 6 DOM 6
Read-only
Reflects the archive attribute of the applet element. Only partially implemented in the browsers. See the discussion of the archive attribute in Chapter 8.

Example
if (document.applets["clock"].archive == "myClock.zip") {
    // process for the found class file
}
Value

Case-sensitive URI as a string.

Default

None.

code NN 6 IE 4 DOM 1
Read-only
Provides the name of the Java applet class file set to the code attribute. Not fully implemented in Netscape 7.

Example

if (document.applets["clock"].code == "XMAScounter.class") { // process for the found class file }

Value

Case-sensitive applet class filename as a string.

Default

None.

codeBase NN 6 IE 4 DOM 1
Read-only
Provides the path to the directory holding the class file designated in the code attribute. The codebase attribute does not name the class file, just the path. Not fully implemented in Netscape 7.

Example

if (document.applets["clock"].codeBase == "classes") { // process for the found class file directory }

Value

Case-sensitive pathname, usually relative to the directory storing the current HTML document.

Default

None.

dataFld NN n/a IE 4 DOM n/a
Read/Write
It is unclear how you would use this property with an applet object because the dataFld and dataSrc properties (as set in element attributes) are applied to individual param elements.

Value

Case-sensitive identifier of the data source column.

Default

None.

dataSrc NN n/a IE 4 DOM n/a
Read/Write
It's unclear how you would use this property with an applet object because the dataFld and dataSrc properties (as set in element attributes) are applied to individual param elements.

Value

Case-sensitive identifier of the data source.

Default

None.

height, width NN 6 IE 4 DOM 1
Read/Write
Indicate the height and width in pixels of the element as set by the tag attributes. Changing the values does not necessarily change the actual rectangle of the applet after it has loaded. Not fully implemented in Netscape 7.

Example

var appletHeight = document.myApplet.height;

Value

Integer.

Default

None.

hspace, vspace NN 6 IE 4 DOM 1
Read/Write
Indicate the pixel measure of horizontal and vertical margins surrounding an applet. The hspace property affects the left and right edges of the element equally; the vspace affects the top and bottom edges of the element equally. These margins are not the same as margins set by style sheets, but they have the same visual effect.

Example

document.getElementById("myApplet").hspace = 5; document.getElementById("myApplet").vspace = 8;

Value

Integer of pixel count.

Default

0

name NN 6 IE 4 DOM 1
Read-only
This is the identifier associated with the applet. Use the name when referring to the object in the form document.appletName.

Value

Case-sensitive identifier that follows the rules of identifier naming: it may contain no whitespace, cannot begin with a numeral, and should avoid punctuation except for the underscore character.

Default

None.

object NN n/a IE 4 DOM n/a
Read-only
Returns a reference to the applet object so that a script can access a property or method of the applet whose name is identical to a property or method of the applet element object.

Value

Applet object (not the applet element object) reference.

Default

None.

src NN n/a IE 4 DOM n/a
Read-only
Internet Explorer defines this attribute as the URL for an associated file. The src property is not a substitute for the code and/or codebase properties.

Value

Complete or relative URL as a string.

Default

None.

vspace
See hspace.

width
See height.

applets NN 2 IE 3 DOM 1

A collection of all the Java applets in the current element, sorted in source code order. Navigator and Internet Explorer let you use array notation to access a single applet in the collection (e.g., document.applets[0], document.applets["clockApplet"]). Internet Explorer allows the index value to be placed inside parentheses instead of brackets (e.g., document.applets(0)). If you wish to use the applet's name as an index value (always as a string identifier), use the value of the name attribute rather than the id attribute. To use the id attribute in a reference to an applet, access the object via a document.all.elementID (in IE only) or document.getElementById("elementID") reference.

Object Model Reference

document.applets[i]

Object-Specific Properties

length

Object-Specific Methods

item( )

namedItem( )

length NN 2 IE 3 DOM 1
Read-only
Returns the number of elements in the collection.

Example

var howMany = document.applets.length;

Value

Integer.

item( ) NN 6 IE 4 DOM 1
item(index[, subindex]) item(index)
Returns a single applet object or collection of applet objects corresponding to the element matching the index value (or, optionally in IE, the index and subindex values).

Returned Value

One applet object or collection (array) of applet objects. If there are no matches to the parameters, the returned value is null.

Parameters

index

When the parameter is a zero-based integer, the returned value is a single element corresponding to the specified item in source code order (nested within the current element); when the parameter is a string, the returned value is a collection of elements whose id or name properties match that string.

subindex

In IE only, if you specify a string value for the first parameter, you can use the second parameter to specify a zero-based index that retrieves the specified element from the collection whose id or name properties match the first parameter's string value.

namedItem( ) NN 6 IE 6 DOM 1
namedItem(IDOrName)
Returns a single applet object or collection of applet objects corresponding to the element matching the parameter string value.

Returned Value

One applet object or collection (array) of applet objects. If there are no matches to the parameters, the returned value is null.

Parameters

IDOrName

The string that contains the same value as the desired element's id or name attribute.

area NN 3 IE 4 DOM 1

The area object reflects the area element, which defines the shape, coordinates, and destination of a clickable region of a client-side image map. Navigator and Internet Explorer treat an area object as a member of the links collection, since an area object behaves much like a link, but for a segment of an image.

HTML Equivalent

<area>

Object Model Reference

[window.]document.links[i]
[window.]document.getElementById("elementID")

Object-Specific Properties

`alt`	`coords`	`hash`	`host`	`hostname`
`href`	`noHref`	`pathname`	`port`	`protocol`
`search`	`shape`	`target`

Object-Specific Methods

None.

Object-Specific Event Handler Properties

None.

alt NN 6 IE 4 DOM 1
Read/Write
Future nongraphical browsers may use the alt property setting to display a brief description of the meaning of the (invisible) image's hotspots.

Example

document.getElementById("elementID").alt = "To Next Page";

Value

Any quoted string of characters.

Default

None.

coords NN 6 IE 4 DOM 1
Read/Write
Defines the outline of the area to be associated with a particular link or scripted action. Coordinate values are entered as a comma-delimited list. If hotspots of two areas should overlap, the area that is defined earlier in the code takes precedence.

Example

document.getElementById("mapArea2").coords = "25, 5, 50, 70";

Value

Each coordinate is a pixel length value, but the number of coordinates and their order depend on the shape specified by the shape attribute, which may optionally be associated with the element. For shape="rect", there are four coordinates (left, top, right, bottom); for shape="circle", there are three coordinates (center-x, center-y, radius); for shape="poly", there are two coordinate values for each point that defines the shape of the polygon.

Default

None.

hash NN 2 IE 3 DOM 1
Read/Write
This is that portion of the href attribute's URL following the # symbol, referring to an anchor location in a document. Do not include the # symbol when setting the property.

Example

document.getElementById("mapArea2").hash = "section3";

Value

String.

Default

None.

host NN 2 IE 3 DOM 1
Read/Write
Provides the combination of the hostname and port (if any) of the server of the destination document for the area link. If the port is explicitly part of the URL, the hostname and port are separated by a colon, just as they are in the URL. If the port number is not specified in an HTTP URL for IE, it automatically returns the default, port 80.

Example

document.getElementById("mapArea2").host = "www.megacorp.com:80";

Value

String of hostname optionally followed by a colon and port number.

Default

Depends on server.

hostname NN 2 IE 3 DOM 1
Read/Write
Provides the hostname of the server (i.e., a two-dot address consisting of server name and domain) of the destination document for the area link. The hostname property does not include the port number.

Example

document.links[2].hostname = "www.megacorp.com";

Value

String of hostname (server and domain).

Default

Depends on server.

href NN 2 IE 3 DOM 1
Read/Write
This is the URL specified by the element's href attribute.

Example

document.links[2].href = "http://www.megacorp.com";

Value

String of complete or relative URL.

Default

None.

noHref NN 6 IE 4 DOM 1
Read/Write
Specifies whether the area defined by the coordinates has a link associated with it. When you set this property to true, scriptable browsers no longer treat the element as a link.

Example

document.links[4].noHref = "true";

Value

Boolean value: true | false.

Default

false

pathname NN 2 IE 3 DOM 1
Read/Write
Provides the pathname component of the URL assigned to the element's href attribute. This consists of all URL information following the last character of the domain name, including the initial forward slash symbol.

Example

document.getElementById("myLink").pathname = "/images/logoHiRes.gif";

Value

String.

Default

None.

port NN 2 IE 3 DOM 1
Read/Write
Provides the port component of the URL assigned to the element's href attribute. This consists of all URL information following the colon after the last character of the domain name. The colon is not part of the port property value.

Example

document.getElementById("myLink").port = "80";

Value

String (a numeric value as string).

Default

None.

protocol NN 2 IE 3 DOM 1
Read/Write
Indicates the protocol component of the URL assigned to the element's href attribute. This consists of all URL information up to and including the first colon of a URL. Typical values are "http:", "file:", "ftp:", and "mailto:".

Example

document.getElementById("secureLink").protocol = "https:";

Value

String.

Default

None.

search NN 2 IE 3 DOM 1
Read/Write
This is the URL-encoded portion of a URL assigned to the href attribute that begins with the ? symbol. A document that is served up as the result of the search also may have the search portion available as part of the window.location property. You can modify this property with a script. Doing so sends the URL and search criteria to the server. You must know the format of data (usually name/value pairs) expected by the server to perform this properly.

Example

document.getElementById("searchLink").search="?p=Tony+Blair&d=y&g=0&s=a&w=s&m=25";

Value

String starting with the ? symbol.

Default

None.

shape NN 6 IE 4 DOM 1
Read/Write
Indicates the shape of a server-side image map area with coordinates that are specified with the coords attribute.

Example

document.getElementById("area51").shape = "circle";

Value

Case-insensitive shape constant as string: default | rect | rectangle | circle | poly | polygon.

Default

RECT (IE); empty string but rect implied (Netscape 6).

target NN 2 IE 3 DOM 1
Read/Write
This is the name of the window or frame that is to receive content as the result of navigating to an area link. Such names are assigned to frames by the frame element's name attribute; for subwindows, the name is assigned via the second parameter of the window.open( ) method. If you need the services of a target attribute to open a linked page in a blank browser window and you also need the HTML to validate under strict HTML or XHTML DTDs, you can omit the target attribute in the code, but assign a value to the area element's target property by script after the page loads.

Example

document.getElementById("homeArea").target = "_blank";

Value

String value of the window or frame name, or any of the following constants (as a string): _parent | _self | _top | _blank. The _parent value targets the frameset to which the current document belongs; the _self value targets the current window; the _top value targets the main browser window, thereby eliminating all frames; and the _blank value creates a new window of default size.

Default

None.

areas NN 6 IE 4 DOM 1

A collection of all area elements associated with a map element. Notice that individual items of an areas collection are also members of the document-wide links collection (document.links[] array). But the members of an areas collection are local to a single map element.

Object Model Reference

document.getElementById("mapElementID").areas

Object-Specific Properties

length

Object-Specific Methods

item( )

namedItem( )

tags( )

urns( )

length NN 6 IE 4 DOM 1
Read-only
Returns the number of elements in the collection.

Example

var howMany = document.areas.length;

Value

Integer.

item( ) NN 6 IE 4 DOM 1
item(index[, subindex]) item(index)
Returns a single area object or collection of area objects corresponding to the element matching the index value (or, optionally in IE, the index and subindex values).

Returned Value

One area object or collection (array) of area objects. If there are no matches to the parameters, the returned value is null.

Parameters

index

When the parameter is a zero-based integer, the returned value is a single element corresponding to the specified item in source code order (nested within the current element); when the parameter is a string, the returned value is a collection of elements whose id or name properties match that string.

subindex

In IE only, if you specify a string value for the first parameter, you can use the second parameter to specify a zero-based index that retrieves the specified element from the collection whose id or name properties match the first parameter's string value.

namedItem( ) NN 6 IE 6 DOM 1
namedItem(IDOrName)
Returns a single area object or collection of area objects corresponding to the element matching the parameter string value.

Returned Value

One area object or collection (array) of area objects. If there are no matches to the parameters, the returned value is null.

Parameters

IDOrName

The string that contains the same value as the desired element's id or name attribute.

tags( ) NN n/a IE 4 DOM n/a
tags(tagName)
Returns a collection of objects (among all objects nested within the current collection) with tags that match the tagName parameter. Implemented in all IE collections (see the all.tags( ) method), but redundant for collections of the same element type.

urns( ) NN n/a IE 5(Win) DOM n/a
urns(URN)
See the all.urns( ) method.

Attr, attribute NN 6 IE 5 DOM 1

An abstract representation of an element's attribute name/value pair is an object known in the W3C DOM vernacular as the Attr object; in IE terminology, it is called an attribute object. They are different names for the same object. An attribute object is created in both environments via the document.createAttribute( ) method; the reference to the attribute object then becomes the parameter to an element's setAttributeNode( ) method to insert that attribute object into the element. For example:

var newAttr = document.createAttribute("author");
newAttr.value = "William Shakespeare";
document.getElementById("hamlet").setAttributeNode(newAttr);

Some W3C DOM element methods (most notably, the getAttributeNode( ) method) return attribute objects, which have properties that may be accessed like any scriptable object.

In the W3C DOM abstract model, the Attr object inherits all properties and methods of the Node object. Some Node object properties, however, are not inherited by the attribute object in IE/Windows until Version 6, even though they are implemented for element and text nodes in Version 5.

HTML Equivalent

Any name/value pair inside a start tag.

Object Model Reference

[window.]document.getElementById("elementID").attributes[i]
[window.]document.getElementById("elementID").attributes.item(i)
[window.]document.getElementById("elementID").attributes.getNamedItem[attrName]

Object-Specific Properties

expando

name

ownerElement

specified

value

Object-Specific Methods

None.

Object-Specific Event Handler Properties

None.

expando NN n/a IE 6 DOM n/a
Read-only
Returns Boolean true if the attribute, once it is inserted into an element, is not one of the native attributes for the element. This property is false for an attribute created by document.createAttribute( ) until the attribute is added to the element (via the setAttributeNode( ) method), at which time the property's value is reevaluated within the context of the element's native attributes.

Example

var isCustomAttr = document.getElementById("book3928").getAttributeNode("author").expando;

Value

Boolean value: true | false.

Default

false

name NN 6 IE 5 DOM 1
Read-only
This is the name portion of the name/value pair of the attribute. It is identical to the nodeName property of the Attr node. You may not modify the name of an attribute by script because other dependencies may lead to document tree confusion. Instead, replace the old attribute with a newly created one, the name of which is a required parameter of the document.createAttribute( ) method.

Example

if (myAttr.name == "author") { // process author attribute }

Value

String value.

Default

Empty string, although creating a new attribute requires a name.

ownerElement NN 6 IE n/a DOM 2
Read-only
Refers to the element that contains the current attribute object. Until a newly created attribute is inserted into an element, this property is null.

Example

if (myAttr.ownerElement.tagName == "fred") { // process attribute of <fred> element }

Value

Element node reference.

Default

null

specified NN 6 IE 5 DOM 1
Read-only
Returns Boolean true if the value of the attribute is explicitly assigned in the source code or adjusted by script. If the browser reflects an attribute that is not explicitly set (IE does this), the specified property for that value is false, even though the attribute may have a default value determined by the document's DTD. The W3C DOM Level 2 indicates that the specified property of a freshly created Attr object should be true, but both IE 6 and Netscape 6.2 and later leave it false until the attribute is inserted into an element.

Example

if (myAttr.specified) { // process attribute whose value is something other than DTD default }

Value

Boolean value: true | false.

Default

false

value NN 6 IE 6 DOM 1
Read/Write
Provides the value portion of the name/value pair of the attribute. Identical to the nodeValue property of the Attr node, as well as data accessed more directly via an element's getAttribute( ) and setAttribute( ) methods. If you create a new attribute object, you can assign its value via the value property prior to inserting the attribute into the element. Attribute node values are always strings, including in IE, which otherwise allows Number or Boolean data types for the corresponding properties.

Example

document.getElementById("hamlet").getAttributeNode("author").value = "Shakespeare";

Value

String value.

Default

Empty string, except in IE/Windows, which returns the string undefined (that is, not a value whose type evaluates to the undefined value).

attributes, NamedNodeMap NN 6 IE 5 DOM 1

The object returned by the attributes property of every W3C DOM element object is a collection (array) of references to Attr (a.k.a. attribute) objects. An attribute type of node always has a name associated with it, which opens the way for methods of the collection of such nodes to access them directly by name, rather than iterating through the array in search of a matching node name. In the W3C DOM structure, the abstract representation of this array of named nodes is called the NamedNodeMap object, which shares some properties and methods of the IE attributes object. Since both objects refer to the same parts of a document tree, they are treated here together. A couple of other W3C DOM collections are also of the NamedNodeMap variety, but your primary contact with the NamedNodeMap in HTML documents is as a collection of Attr objects. Collection members are sorted in source code order.

There are more direct ways to access an attribute of an element (such as the getAttribute( ) or getAttributeNode( ) methods of all elements). The property and methods shown here, however, assume that your script has been handed a collection of attributes independent of their host element, and your processing starts from that point.

Object Model Reference

elementReference.attributes

Object-Specific Properties

length

Object-Specific Methods

`getNamedItem( )`	`getNamedItemNS( )`	`item( )`	`removeNamedItem( )`
`removeNamedItemNS( )`	`setNamedItem( )`	`setNamedItemNS( )`

Object-Specific Event Handler Properties

None.

length NN 6 IE 5 DOM 1
Read-only
Returns the number of elements in the collection.

Example

var howMany = document.getElementById("myTable").attributes.length;

Value

Integer.

getNamedItem( ) NN 6 IE 6 DOM 1
getNamedItem("attributeName")
Returns a single Attr object corresponding to the attribute whose node name matches the parameter value.

Returned Value

Reference to one Attr object. If there is no match to the parameter value, the returned value is null.

Parameters

attributeName

String corresponding to the name portion of an attribute's name/value pair.

getNamedItemNS( ) NN 6 IE n/a DOM 2
getNamedItemNS("namespaceURI", "localName")
Returns a single Attr object with a local name and namespace URI that match the parameter values.

Returned Value

Reference to one Attr object. If there is no match to the parameter values, the returned value is null.

Parameters

namespaceURI

URI string matching a URI assigned to a label earlier in the document.

localName

The local name portion of the attribute.

item( ) NN 6 IE 5 DOM 1
item(index)
Returns a single Attr object corresponding to the element matching the index value.

Returned Value

Reference to one Attr object. If there is no match to the index value, the returned value is null. Unlike some other collections in IE, a string index value is not allowed for the attributes object.

Parameters

index

A zero-based integer corresponding to the specified item in source code order.

removeNamedItem( ) NN 6 IE 6 DOM 1

`alternate`	`appendix`	`bookmark`	`chapter`	`contents`
`copyright`	`glossary`	`help`	`index`	`next`
`prev`	`section`	`start`	`stylesheet`	`subsection`

9.6. Alphabetical Object Reference

HTML Equivalent

Object Model Reference

Object-Specific Properties

Object-Specific Methods

Object-Specific Event Handler Properties

Example

Value

Default

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