HTML4.01规范中英文对照-HTML基本数据类型(2)

6.11 Dates and times

[ISO8601] allows many options and variations in the representation of dates and times. The current specification uses one of the formats described in the profile [DATETIME] for its definition of legal date/time strings ( %Datetime in the DTD).

[ISO8601]在日期和时间的展现上允许很多选项及变形。本规范只采用了其中的一种格式，在[DATETIME] 中描述了该格式的细节，在DTD的参数实体%Datetime 中出现的日期/时间字符串必须符合该种格式才是合法的。

The format is:

  YYYY-MM-DDThh:mm:ssTZD

where:

     YYYY = four-digit year

     MM   = two-digit month (01=January, etc.)
     
DD   = two-digit day of month (01 through 31)
     
hh   = two digits of hour (00 through 23) (am/pm NOT allowed)
     
mm   = two digits of minute (00 through 59)
     
ss   = two digits of second (00 through 59)
     
TZD  = time zone designator

The time zone designator is one of:

Z

indicates UTC (Coordinated Universal Time). The "Z" must be uppercase.

+hh:mm

indicates that the time is a local time which is hh hours and mm minutes ahead of UTC.

-hh:mm

indicates that the time is a local time which is hh hours and mm minutes behind UTC.

日期/时间字符串的格式如下：

  YYYY-MM-DDThh:mm:ssTZD

其中：

     YYYY = 四位数字的年份
     MM   = 两位数字的月份(01代表一月份，依此类推)
     
DD   = 两位数字的日期(从01 到 31)
     
hh   = 两位数字的小时(从00 到 23) (不允许上下午标识：am/pm)
     
mm   = 两位数字的分钟(从00 到 59)
     
ss   = 两位数字的秒钟(从00 到 59)
     
TZD  = 时区指示符

时区指示符可以是下表中的任何一种：

Z

代表UTC时间即协调世界时。 "Z" 必须大写。

+hh:mm

代表该时间是本地时间，该时间在UTC时间之前hh小时mm分钟。

-hh:mm

代表该时间是本地时间，该时间在UTC时间之后hh小时mm分钟。

Exactly the components shown here must be present, with exactly this punctuation. Note that the "T" appears literally in the string (it must be uppercase), to indicate the beginning of the time element, as specified in [ISO8601]

必须按照上面的描述提供所有组成部分，它们之间的标点分隔也要精确匹配。请注意：根据[ISO8601]的描述，大写字符"T"（必须大写）表示时间元素的开始。

If a generating application does not know the time to the second, it may use the value "00" for the seconds (and minutes and hours if necessary).

如果生成程序不知道具体的秒钟时间，它可以对秒钟字段使用"00"作为其值。类似的，如果需要也可以将该规则应用到分钟，小时字段。

Note. [DATETIME] does not address the issue of leap seconds.

注释。 [DATETIME] 不包括闰秒机制。

6.12 Link types

Authors may use the following recognized link types, listed here with their conventional interpretations. In the DTD, %LinkTypes refers to a space-separated list of link types. White space characters are not permitted within link types.

HTML作者可以使用下述已经被识别出链接类型，这些链接类型在下表中都有规范的解释。在DTD中， %LinkTypes 指的是用空格分隔的链接类型列表。在链接类型里不允许出现空格字符。

These link types are case-insensitive, i.e., "Alternate" has the same meaning as "alternate".

这些链接类型是大小写不敏感的，例如： "Alternate"和"alternate"都代表同样的含义。

User agents, search engines, etc. may interpret these link types in a variety of ways. For example, user agents may provide access to linked documents through a navigation bar.

用户代理、搜索引擎等等可能会对这些链接类型进行不同方式的解读。例如：用户代理可能会通过导览条提供对链接文档的访问机制。

Alternate

Designates substitute versions for the document in which the link occurs. When used together with the lang attribute, it implies a translated version of the document. When used together with the media attribute, it implies a version designed for a different medium (or media).

Alternate型的链接为文档指定了替代版本。当和lang属性一起使用时，表示一个当前文档的相应翻译版本。当和media属性一起使用时，表示为另外一种不同的介质（媒体）设计的文档版本。

Stylesheet

Refers to an external style sheet. See the section on external style sheets for details. This is used together with the link type "Alternate" for user-selectable alternate style sheets.

指向外部样式表。有关详细信息，请参阅“外部样式表”部分。当其和链接类型"Alternate"一起使用时，可以表示用户可选择的替代样式表。

Start

Refers to the first document in a collection of documents. This link type tells search engines which document is considered by the author to be the starting point of the collection.

只是文档集合中的第一个文档。该链接类型可以告知搜索引擎哪一个文档是作者认为的集合起始点。

Next

Refers to the next document in a linear sequence of documents. User agents may choose to preload the "next" document, to reduce the perceived load time.

指向在一组线性排列的文档中，下一个文档。用户代理可以选择提前装载"next"所指定的文档，这样做可以减少文档装载感知时间。

Prev

Refers to the previous document in an ordered series of documents. Some user agents also support the synonym "Previous".

指向在一组排序的文档中，前一个文档。有一些用户代理同时支持同义词"Previous"。

Contents

Refers to a document serving as a table of contents. Some user agents also support the synonym ToC (from "Table of Contents").

指向一个作为目录的文档。一些用户代理同时支持同义词ToC(即英文：“Table of Contents”)。

Index

Refers to a document providing an index for the current document.

指向为当前文档提供索引的文档.

Glossary

Refers to a document providing a glossary of terms that pertain to the current document。

指向为当前文档中出现的术语提供术语列表的文档。

Copyright

Refers to a copyright statement for the current document.

指向当前文档的版权声明。

Chapter

Refers to a document serving as a chapter in a collection of documents.

指向在文档集合中作为一章的文档。

Section

Refers to a document serving as a section in a collection of documents.

指向在一个文档集合中作为部分（Section)的文档。

Subsection

Refers to a document serving as a subsection in a collection of documents

指向一个文档集合中作为子部分的文档。

Appendix

Refers to a document serving as an appendix in a collection of documents

指向一个文档集合中作为附录的文档。.

Help

Refers to a document offering help (more information, links to other sources information, etc.）

指向一个提供帮助信息的文档，该文档比如有更多信息以及链接到其他信息源等。

Bookmark

Refers to a bookmark. A bookmark is a link to a key entry point within an extended document. The title attribute may be used, for example, to label the bookmark. Note that several bookmarks may be defined in each document.

指向一个书签。书签是指向到文档内关键入口的链接。title属性可以被用来标记命名书签。请注意，在一个文档内可以定义多个书签。

Authors may wish to define additional link types not described in this specification. If they do so, they should use a profile to cite the conventions used to define the link types. Please see the profile attribute of the HEAD element for more details.

HTML作者可能希望定义其他本规范内没有描述的链接类型。如果他们确实想这么做，那么他们应该使用profile注解用于定义链接类型的术语。请参考HEAD元素的profile属性来获得更多细节。

For further discussions about link types, please consult the section on links in HTML documents.

关于链接类型的更深入讨论，请参阅《HTML文档内的链接》部分。

6.13 Media descriptors

The following is a list of recognized media descriptors ( %MediaDesc in the DTD).

下面是已经可以被识别的介质描述列表,媒体描述符在DTD中用参数实体%MediaDesc来表示。

screen

Intended for non-paged computer screens。

没有分页机制的计算机屏幕。

tty

Intended for media using a fixed-pitch character grid, such as teletypes, terminals, or portable devices with limited display capabilities

固定字符网格型介质，例如，电传打字机机，字符终端，显示能力有限的移动设备。

tv

Intended for television-type devices (low resolution, color, limited scrollability)

电视类型的设备,这种类型的设备特性是低分辨率，颜色少，滚动能力受限。

projection

Intended for projectors.

投影仪。

handheld

Intended for handheld devices (small screen, monochrome, bitmapped graphics, limited bandwidth)

手持设备，这种类型的设备的特性如下：屏幕尺寸小，一般只有黑白显示，无彩色，只支持位图形式的图片以及网络传输带宽也比较有限。

print

Intended for paged, opaque material and for documents viewed on screen in print preview mode。

分页的不透明的物质以及在屏幕上以打印预览模式显示。

braille

Intended for braille tactile feedback devices

盲文触感回馈设备。

aural

Intended for speech synthesizers.

语音合成器。

all

Suitable for all devices.

适合于所有设备。

Future versions of HTML may introduce new values and may allow parameterized values. To facilitate the introduction of these extensions, conforming user agents must be able to parse the media attribute value as follows:

在HTML的未来版本中可能会引入更多的介质名称并且可能允许参数化取值。为了简化这些可能的扩展，符合规范的用户代理必须能按照如下的机制来解析media属性的值：

1. The value is a comma-separated list of entries. For example,

   media="screen, 3d-glasses, print and resolution > 90dpi"
   

   is mapped to:

   "screen"
   "3d-glasses"
   "print and resolution > 90dpi"
   

2. Each entry is truncated just before the first character that isn't a US ASCII letter [a-zA-Z] (ISO 10646 hex 41-5a, 61-7a), digit [0-9] (hex 30-39), or hyphen (hex 2d). In the example, this gives:

   "screen"
   "3d-glasses"
   "print"
   

3. A case-sensitive match is then made with the set of media types defined above. User agents may ignore entries that don't match. In the example we are left with screen and print.

1. media属性值的形式是用逗号分隔的实体列表。例如,

   media="screen, 3d-glasses, print and resolution > 90dpi"
   

   会被映射为:

   "screen"
   "3d-glasses"
   "print and resolution > 90dpi"三个实体。
   

2. 对于实体，如果其内包含非US ASCII字符[a-zA-Z] (ISO 10646 十六进制代码 41-5a, 61-7a), 数字 [0-9] (十六进制代码 30-39), 连词符(十六进制代码 2d)，那么该实体会被截断，截断的位置为第一个非法字符之前。继续上面的例子, 这会使上面的三个实体变成：

   "screen"
   "3d-glasses"
   "print"
   

3. 然后将得到的实体列表与本节开始定义的介质类型进行区分大小写的匹配。用户代理可以忽略那些没有匹配到的实体。继续上面的例子，就会只剩 screen 和 print

Note. Style sheets may include media-dependent variations within them (e.g., the CSS @media construct). In such cases it may be appropriate to use "media=all".

注释。样式表可能包含上述介质的更多变种（例如，CSS @media指令）。在这种情况下，将media设置成all可能更合适。

6.14 Script data

Script data ( %Script; in the DTD) can be the content of the SCRIPT element and the value of intrinsic event attributes. User agents must not evaluate script data as HTML markup but instead must pass it on as data to a script engine.

Script脚本数据（在DTD中%Script;参数实体）可以是SCRIPT元素的内容或者死内建时间属性的属性值。用户代理绝对不能将脚本数据当做HTML标记处理，而是要将它当成数据传递给相应的脚本引擎。

The case-sensitivity of script data depends on the scripting language.

Script脚本数据是否大小写敏感依赖于相应的脚本语言。

Please note that script data that is element content may not contain character references, but script data that is the value of an attribute may contain them. The appendix provides further information about specifying non-HTML data.

请注意，当Script脚本数据是元素内容的时候，不能含有字符引用。但当Script脚本数据是属性值时就可以携带字符引用。附录里提供了关于指定非HTML数据的更进一步信息。

6.15 Style sheet data

Style sheet data (%StyleSheet; in the DTD) can be the content of the STYLE element and the value of the style attribute. User agents must not evaluate style data as HTML markup.

样式表数据（在DTD中为%StyleSheet;参数实体）可以是STYLE元素的内容，另外也可以是style属性的值。用户代理绝对不能将样式表数据当成HTML标记来处理。

The case-sensitivity of style data depends on the style sheet language.

样式数据是否是大小写敏感依赖于相应的样式表语言。

Please note that style sheet data that is element content may not contain character references, but style sheet data that is the value of an attribute may contain them. The appendix provides further information about specifying non-HTML data.

请注意，样式表数据作为元素内容时不可以携带字符引用，但作为属性值时可以携带字符引用。附录里提供了有关指定非HTML数据的更进一步信息。

6.16 Frame target names

Except for the reserved names listed below, frame target names (%FrameTarget; in the DTD) must begin with an alphabetic character (a-zA-Z). User agents should ignore all other target names.

除了下表列出的保留的名字外，框架目标名字（在DTD中的%FrameTarget参数实体）必须以字母开始（a-zA-Z）。用户代理应该忽略其他任何形式的目标名字。

The following target names are reserved and have special meanings.

下面的目标名字是被保留并有特使含义的。

_blank

The user agent should load the designated document in a new, unnamed window

用户代理应该一个全新的未命名的窗口中载入指定的文档。

_self

The user agent should load the document in the same frame as the element that refers to this target

用户代理应该在引用到该目标的元素所在的框架（frame）中载入文档。

_parent

The user agent should load the document into the immediate FRAMESET parent of the current frame. This value is equivalent to _self if the current frame has no parent

用户代理应该将文档载入到当前框架的直接的父FRAMESET中。如果当前框架没有父节点，那么该值与_self相同。

_top

The user agent should load the document into the full, original window (thus canceling all other frames). This value is equivalent to _self if the current frame has no parent

用户代理应该将文档载入到那个完整的原始窗口（于是取消了所有其他的框架）。如果当前框架没哟父节点，该值与_self相同。