容器

   <OBJECT classid="http://www.miamachina.it/analogclock.py"> 
<PARAM name="height" value="40" valuetype="data"> 
<PARAM name="width" value="40" valuetype="data"> This user agent cannot render Python apps. 
</OBJECT>

? <PARAM name="height" value="40"> <PARAM name="width" value="40" >

? <PARAM name="height" value="40" data> <PARAM name="width" value="40"?data>

<OBJECT classid="http://www.gifstuff.com/gifappli"     standby="Loading Elvis..."> 
<PARAM name="Init_values"     value="./images/elvis.gif">     valuetype="ref"> </OBJECT>

<OBJECT classid="java:program.start"> </OBJECT>

<OBJECT codetype="application/octet-stream"       classid="java:program.start"> </OBJECT>

<OBJECT codetype="application/octet-stream"       classid="java:program.start">       
codebase="http://foooo.bar.com/java/myimplementation/" </OBJECT>

<OBJECT classid="clsid:663C8FEF-1EF9-11CF-A3DB-080036F12502"       data="http://www.acme.com/ole/clock.stm"> 
This application is not supported. </OBJECT>

Object declarations and instantiations

• Data may be retrieved from the network by the user agent one time (during the declaration)and reused for each instantiation.
• It is possible to instantiate an object from a different location in the document,for example,by activating a link.
• It is possible to specify objects as run-time data for other objects.

Arendering mechanism defined with the declare attribute is instantiated every time the OBJECT is referenced thereafter.

<OBJECT declare       id="earth_declaration"?       data="TheEarth.mpeg"?       type="application/mpeg"> 
<OBJECT src="TheEarth.gif">   The <STRONG>Earth</STRONG> as seen from space. ?</OBJECT> </OBJECT>
...later in the document...
Click to see a neat <A href="#earth_declaration"> animation of The Earth!</A>

<OBJECT declare    id="tribune"    type="application/x-webfont"    data="tribune.gif"> </OBJECT>
...view the poem in KublaKhan.txt here...
<OBJECT classid="http://foo.bar.com/poem_viewer"?       data="KublaKhan.txt"> 
<PARAM name="font" valuetype="object" value="#tribune"> 
<P>You're missing a really cool poem viewer ... </OBJECT>

Object alignment

The alignattribute specifies the position of an object with respect to its context.

The following values place an object in the heart of text:

• texttop:means the top of the object should be vertically aligned with the top of the current text line.
• middle:means the middle of the object should be vertically aligned with the current baseline.
• textmiddle:means the middle of the object should be vertically aligned with the position midway between the baseline and the x-height for the current font.The x-height is defined as the top of a lower case x in Western writing systems.If the text font is an all-caps style,user agents should use the height of a capital X.For other writing systems, user agents should align the middle of the object with the middle of the text.
• baseline:means the bottom of the object should be vertically aligned with the current baseline.
• textbottom:means the bottom of the object should be vertically aligned with the bottom of the current text line.

Including an image: the?A NAME="edef-IMG">IMG element

<!-- To avoid problems with text-only UAs you need to provide a description with ALT, and avoid server-side image maps -->
<!ELEMENTIMG - O EMPTY  ?--?Embedded image -->
<!ATTLIST IMG
?%attrs;            ?--%coreattrs,%i18n,%events --
src    %URL   #REQUIRED--URLof image to embed --
alt    CDATA  ?#IMPLIED?--description for text only browsers --
align   %IAlign ?#IMPLIED?--vertical or horizontal alignment --
height  ?%Pixels ?#IMPLIED?--suggested height in pixels --
width   %Pixels ?#IMPLIED?--suggested width in pixels --
border  ?%Pixels ?#IMPLIED?--suggested link border width --
hspace  ?%Pixels ?#IMPLIED?--suggested horizontal gutter --
vspace  ?%Pixels ?#IMPLIED?--suggested vertical gutter --
usemap  ?%URL   #IMPLIED?--use client-side image map --
ismap    (ismap) ?#IMPLIED?-- use server-side image map -- ?>

The heightand widthattributes of this element override the natural height and width of the source image.User agents should scale the image appropriately.

...preceding text...
I just returned from vacation! Here's a photo of my family at the lake: 
<IMG src="http://www.somecompany.com/People/Ian/vacation/family.png"   
alt="A photo of my family at the lake.">

...preceding text...
I just returned from vacation! Here's a photo of my family at the lake: 
<OBJECT data="http://www.somecompany.com/People/Ian/vacation/family.png"    
type="image/png"> A photo of my family at the lake. </OBJECT>

Image alignment

The alignattribute specifies the position of an object with respect to its context.

The following values place an object in the heart of text:

• bottom:means that the bottom of the image should be vertically aligned with the current baseline.This is the default value.
• middle:means that the center of the image should be vertically aligned with the current baseline.
• top:means that the top of the image should be vertically aligned with the top of the current text line.

Including an applet: the?A NAME="edef-APPLET">APPLET element

<!ELEMENTAPPLET - - (PARAM | %inline)*>
<!ATTLIST APPLET
codebase ?%URL   #IMPLIED --optional base URLfor applet --
archive  CDATA  ?#IMPLIED --comma separated archive list --
code   ?CDATA  ?#IMPLIED --applet class file --
object  ?CDATA  ?#IMPLIED --serialized applet file --
alt    CDATA  ?#IMPLIED --description for text only browsers --
name   ?CDATA  ?#IMPLIED --allows applets to find each other --
width   %Pixels ?#REQUIRED?--suggested width in pixels --
height  ?%Pixels ?#REQUIRED?--suggested height in pixels --
align   %IAlign ?#IMPLIED --vertical or horizontal alignment --
hspace  ?%Pixels ?#IMPLIED --suggested horizontal gutter --
vspace  ?%Pixels ?#IMPLIED  -- suggested vertical gutter -- ?>

The content of the APPLET acts as alternate information for user agents that don't support this element or are currently configured not to support applets.The content must be ignored otherwise.

<APPLET code="Bubbles.class" width="500px" height="500px"> Java applet that draws animated bubbles. </APPLET>

<OBJECT codetype="application/octet-stream"    
classid="java:Bubbles.class"    
width="500" height="500px"> Java applet that draws animated bubbles. 
</OBJECT>

<APPLET code="AudioItem" width="15px" height="15px"> 
<PARAM name="snd" value="Hello.au|Welcome.au"> Java applet that plays a welcoming sound. 
</APPLET>

<OBJECT codetype="application/octet-stream"    
classid="AudioItem"    
width="15" height="15px"> 
<PARAM name="snd" value="Hello.au|Welcome.au"> Java applet that plays a welcoming sound. 
</OBJECT>

Including HTMLin another HTMLdocument

...text before...
<OBJECT data="file_to_include.html"> Warning: file_to_include.html could not be included. </OBJECT>
...text after...

Including an image map in an HTMLdocument

An image map is created by associating an object with a specification of sensitive geometric areas on the object.

There are two types of image maps:

• Server-side.When a user activates a region of a server-side image map with a mouse,the pixel coordinates of the click are sent to the server where the document is housed.The server interprets the coordinates and performs some action.
• Client-side.When a user activates a region of a client-side image map with a mouse,the pixel coordinates are interpreted by the user agent. The user agent selects a link that was specified for the activated region and follows it.

Client-side image maps

<OBJECT data="navbar.gif" shapes> 
<A href="guide.html" shape="rect" coords="0,0,118,28">Access Guide
</a> | <A href="shortcut.html" shape="rect" coords="118,0,184,28">Go
</A> | <A href="search.html" shape="circ" coords="184,200,60">Search
</A> | <A href="top10.html" shape="poly" coords="276,0,373,28,50,50,276,0">Top Ten
</A> </OBJECT>

If two or more defined regions overlap,the region defined first takes precedence (i.e.,responds to user input).

Client-side image maps with?A NAME="edef-MAP">MAP and?A NAME="edef-AREA">AREA

<!ELEMENTMAP - - (AREA)*>
<!ATTLIST MAP
%coreattrs;          --id,
class,style,title--
name   ?CDATA   #IMPLIED ?>

<!ELEMENTAREA - O EMPTY>
<!ATTLIST AREA
shape   %Shape ?rect  ?--controls interpretation of coords --
coords  ?%Coords #IMPLIED?--comma separated list of values --
href   ?%URL  ?#IMPLIED?--this region acts as hypertext link --
target  ?CDATA  #IMPLIED?--where to render linked resource --?
nohref  ?(nohref)?#IMPLIED?--this region has no action --
alt    CDATA  #REQUIRED--description for text only browsers --
tabindex ?NUMBER ?#IMPLIED?-- position in tabbing order -- ?>

<OBJECT data="navbar1.gif" usemap="#map1"></OBJECT> <MAP name="map1"> 
<AREA href="guide.html"?     alt="Access Guide"?     ?shape="rect"?     
?coords="0,0,118,28"> <AREA href="search.html"?     ?alt="Search"?     
?shape="rect"?     ?coords="184,0,276,28"> <AREA href="shortcut.html"?     
?alt="Go"?     ?shape=circ?     ?coords="184,200,60"> <AREA href="top10.html"?     
alt="Top Ten"?     ?shape="poly"?     
coords="276,0,373,28,50,50,276,0"> </MAP>

Server-side image maps

It is only possible to define a server-side image map with the IMG element. To do so, set the boolean attributeismap in the IMGdefinition.The associated map of regions must be specified with the usemap attribute.

When the user activates a region of the image map,the screen coordinates are sent directly to the server where the document resides.Screen coordinates are expressed as screen pixel values.For normative information about the definition of a pixel and how to scale it,please consult [CSS1].

The location clicked is passed to the server as follows.The user agent derives a new URLfrom the URLspecified by the href attribute by appending `?'followed by the x and y coordinates,separated by a comma.The link is then followed using the new URL.For instance, in the previous example,if the user clicks at at the location x=10,y=27 then the derived URLis "/cgibin/navbar.map?10,27".

<OBJECT data="game.gif" shapes> ?<A href="guide.html" shape="rect" coords="0,0,118,28">    
Rules of the Game</A> 
<A href="http://www.acme.com/cgi-bin/competition"    ?ismap?    ?shape="default">    
Guess the location</a> 
</OBJECT>

Visual presentation of images,objects,and applets

The heightand widthattributes give user agents an idea of the size of an image or object so that they may reserve space for it and continue rendering the document while waiting for the image data. Both attributes take values of type length. User agents may scale objects and images to match these values if appropriate.

The vspaceand hspaceattributes specify the amount of white space to be inserted to the left and right (hspace)and above and below (vspace)an image or object.The default value for this attribute is not specified,but is generally a small,non-zero length.Both attributes take values of type length.

Images or objects that are the content of an A element are sometimes surrounded by a border.The border attribute specifies the width of this border.

How to specify alternate text

While alternate text may be very helpful,it must be handled with care. Authors should observe the following guidelines:

• Do not specify meaningless alternate text when including images intended to formata page.In this case,the alternate text should be the empty string ("").In any case,authors should not use images to format pages;style sheets should be used instead.
• Do not specify meaningless alternate text (e.g.,"dummy text").Not only will this frustrate users,it will slow down user agents that must convert text to speech or braille output.

When an author does not set the alt attribute for the IMGor APPLETelements,user agents should supply the alternate text,calculated in the following order:

1. If the titlehas been specified, its value should be used as alternate text.
2. Otherwise,if HTTPheaders provide title information when the included object is retrieved,this information should be used as alternate text.
3. Otherwise,if the included object contains text fields (e.g.,GIFimages contain some text fields),information extracted from the text fields should be used as alternate text.Since user agents may have to retrieve an entire object first in order to extract textual information,user agents may adopt more economical approaches (e.g.,content negotiation).
4. Otherwise,in the absence of other information,user agents should use the file name (minus the extension)as alternate text.

1. If the titlehas been specified, its value should be used as alternate text.
2. Otherwise,if the name has been specified,its value should be used as alternate text.
3. Otherwise (submit and reset buttons),the value of the type attribute should be used as alternate text.