HTML 5 教程(三) - 塊級(jí)元素 HTML 5 還增加了一些純語(yǔ)義性的塊級(jí)元素: aside figure dialog 我在文章和書中一直使用前兩個(gè)元素。第三個(gè)元素我不經(jīng)常用,它主要用于書面文本。 aside aside 元素代表說(shuō)明、提示、邊欄、引用、附加注釋等,也就是敘述主線之外的內(nèi)容。例如,在 developerWorks 文章中,常常會(huì)看到用表格形式編寫的邊欄,見(jiàn)代碼3 用 HTML 4 編寫的 developerWorks 邊欄。
.xf-value
The .xf-value selector used here styles the input field value but not its label. This is actually inconsistent with the current CSS3 draft. The example really should use the ::value pseudo-class instead like so:
input::value { width: 20em; }
#ccnumber::value { width: 18em }
#zip::value { width: 12em }
#state::value { width: 3em}
However, Firefox doesn't yet support this syntax.
在 HTML 5 中,可以按照更有意義的方式編寫這個(gè)邊欄,見(jiàn)代碼4 用 HTML 5 編寫的 developerWorks 邊欄。
.xf-value
The .xf-value selector used here styles the input field value but not its label. This is actually inconsistent with the current CSS3 draft. The example really should use the ::value pseudo-class instead like so:
input::value { width: 20em; }
#ccnumber::value { width: 18em }
#zip::value { width: 12em }
#state::value { width: 3em}However, Firefox doesn't yet support this syntax.
瀏覽器可以決定把這個(gè)邊欄放在哪里(可能需要用一點(diǎn)兒 CSS 代碼)。 figure figure 元素代表一個(gè)塊級(jí)圖像,還可以包含說(shuō)明。例如,在許多 developerWorks 文章中,可以看到代碼5 用 HTML 4 編寫的 developerWorks 圖 這樣的標(biāo)記其結(jié)果見(jiàn)圖1。 Figure 2. Install Mozilla XForms dialog
下載 (20.95 KB) 2009-6-12 11:43 圖 1. Install Mozilla XForms dialog 在 HTML 5 中,可以按照更有語(yǔ)義性的方式編寫這個(gè)圖,見(jiàn)代碼6 用 HTML 5 編寫的 developerWorks 圖。 Figure 2. Install Mozilla XForms dialog 最重要的是,瀏覽器(尤其是屏幕閱讀器)可以明確地將圖和說(shuō)明聯(lián)系在一起。 figure 元素不只可以顯示圖片。還可以使用它給 audio、video、iframe、object 和 embed 元素加說(shuō)明。 dialog dialog 元素表示幾個(gè)人之間的對(duì)話。HTML 5 dt 元素可以表示講話者,HTML 5 dd 元素可以表示講話內(nèi)容。所以,在老式瀏覽器中也可以以合理的方式顯示對(duì)話。代碼7 顯示在 Galileo 的 “Dialogue Concerning the Two Chief World Systems” 上的一段著名對(duì)話。 代碼7. 用 HTML 5 編寫的 Galilean 對(duì)話
Simplicius
According to the straight line AF, and not according to the curve, such being already excluded for such a use.
Sagredo
But I should take neither of them, seeing that the straight line AF runs obliquely. I should draw a line perpendicular to CD, for this would seem to me to be the shortest, as well as being unique among the infinite number of longer and unequal ones which may be drawn from the point A to every other point of the opposite line CD.
Salviati
Your choice and the reason you adduce for it seem to me most excellent. So now we have it that the first dimension is determined by a straight line; the second (namely, breadth) by another straight line, and not only straight, but at right angles to that which determines the length. Thus we have defined the two dimensions of a surface; that is, length and breadth.
But suppose you had to determine a height—for example, how high this platform is from the pavement down below there. Seeing that from any point in the platform we may draw infinite lines, curved or straight, and all of different lengths, to the infinite points of the pavement below, which of all these lines would you make use of?
對(duì)于這個(gè)元素的準(zhǔn)確語(yǔ)法還有爭(zhēng)議。一些人希望在 dialog 元素中嵌入非對(duì)話文本(比如劇本中的舞臺(tái)說(shuō)明),還有人不喜歡擴(kuò)展 dt 和 dd 元素的作用。盡管在具體語(yǔ)法方面有爭(zhēng)議,但是大多數(shù)人都認(rèn)為以這樣的語(yǔ)義性方式表達(dá)對(duì)話是好事情。