在HTML中,表格不应该用于布局,这似乎是普遍的观点。

Why?

我从来没有(老实说,很少)看到过支持这一点的有力论据。通常的答案是:

It's good to separate content from layoutBut this is a fallacious argument; Cliche Thinking. I guess it's true that using the table element for layout has little to do with tabular data. So what? Does my boss care? Do my users care?Perhaps me or my fellow developers who have to maintain a web page care... Is a table less maintainable? I think using a table is easier than using divs and CSS.By the way... why is using a div or a span good separation of content from layout and a table not? Getting a good layout with only divs often requires a lot of nested divs. Readability of the codeI think it's the other way around. Most people understand HTML, few understand CSS. It's better for SEO not to use tablesWhy? Can anybody show some evidence that it is? Or a statement from Google that tables are discouraged from an SEO perspective? Tables are slower.An extra tbody element has to be inserted. This is peanuts for modern web browsers. Show me some benchmarks where the use of a table significantly slows down a page. A layout overhaul is easier without tables, see css Zen Garden.Most web sites that need an upgrade need new content (HTML) as well. Scenarios where a new version of a web site only needs a new CSS file are not very likely. Zen Garden is a nice web site, but a bit theoretical. Not to mention its misuse of CSS.

我对使用divs + CSS而不是表的良好参数非常感兴趣。


当前回答

In the past, screen readers and other accessibility software had a difficult time handling tables in an efficient fashion. To some extent, this became handled in screen readers by the reader switching between a "table" mode and a "layout" mode based on what it saw inside the table. This was often wrong, and so the users had to manually switch the mode when navigating through tables. In any case, the large, often highly nested tables were, and to a large extent, are still very difficult to navigate through using a screen reader.

The same is true when divs or other block-level elements are used to recreate tables and are highly nested. The purpose of divs is to be used as a fomating and layout element, and as such, are intended used to hold similar information, and lay it out on the screen for visual users. When a screen reader encounters a page, it often ignores any layout information, both CSS based, as well as html attribute based(This isn't true for all screen readers, but for the most popular ones, like JAWS, Windows Eyes, and Orca for Linux it is).

为此,表格式数据,也就是逻辑上有意义的在二维或多维维度中排序的数据,具有某种标题,最好放在表中,并使用div来管理页面上内容的布局。(另一种思考“表格数据”的方式是尝试以图表形式绘制它……如果你不能,它可能不是最好的表示在一个表中)

Finally, with a table-based layout, in order to achieve a fine-grained control of the position of elements on the page, highly nested tables are often used. This has two effects: 1.) Increased code size for each page - Since navigation and common structure is often done with the tables, the same code is sent over the network for each request, whereas a div/css based layout pulls the css file over once, and then uses less wordy divs. 2.) Highly nested tables take much longer for the client's browser to render, leading to slightly slower load times.

在这两种情况下,“最后一英里”带宽的增加,以及更快的个人电脑缓解了这些因素,但它们仍然是许多网站存在的问题。

With all of this in mind, as others have said, tables are easier, because they are more grid-oriented, allowing for less thought. If the site in question is not expected to be around long, or will not be maintained, it might make sense to do what is easiest, because it might be the most cost effective. However, if the anticipated userbase might include a substantial portion of handicapped individuals, or if the site will be maintained by others for a long time, spending the time up front to do things in a concise, accessible way may payoff more in the end.

其他回答

对我来说,一个巨大的问题是,表,特别是嵌套表,需要更长的时间来呈现比一个正确布局的css实现。(你可以让css一样慢)。

所有浏览器呈现css的速度都更快,因为每个div都是一个单独的元素,所以用户在阅读时可以加载屏幕。(对于庞大的数据集等)。我在那个实例中使用了css而不是表格,甚至没有处理布局。

嵌套的表(单元格中的表等)直到找到最后一个“/table”才会呈现到浏览器窗口。更糟糕的是,定义不清的表有时甚至无法呈现!或者当它发生的时候,事情就会不正常。(没有正确地与“TD”等共进)

我在大多数情况下使用表格,但当涉及到大数据和希望为最终用户快速呈现屏幕时,我尽最大努力利用CSS所提供的东西。

根据508法规(对于视障屏幕阅读器),表格应该只用于保存数据,而不是用于布局,因为它会导致屏幕阅读器崩溃。至少别人是这么告诉我的。

如果您为每个div分配名称,您也可以使用CSS将它们一起蒙皮。只是让他们坐成你想要的样子有点麻烦。

我曾经了解到,一个表是立即加载的,换句话说,当连接很慢的时候,表所在的空间保持空白,直到整个表被加载,另一方面,一个div加载从上到下的速度与数据到达的速度一样快,不管它是否已经完成。

无论如何,这并不是一个明确的论点,但是对于CSS,你可以使用相同的标记并根据介质改变布局,这是一个很好的优势。例如,对于打印页面,您可以安静地抑制导航,而不必创建打印机友好的页面。

将内容与布局分开是很好的 但这是一个错误的论点;陈词滥调的思考

这是一个错误的论点,因为HTML表格是布局!内容是表中的数据,表示是表本身。这就是为什么从HTML中分离CSS有时会非常困难。您不是将内容与表示分开,而是将表示与表示分开!一堆嵌套的div和一个表没有什么不同——它只是一组不同的标签。

把HTML和CSS分开的另一个问题是,它们需要彼此的密切了解——你真的不能把它们完全分开。无论您做什么,HTML中的标记布局都与CSS文件紧密耦合。

我认为表与div的区别取决于应用程序的需要。

在我们在工作中开发的应用程序中,我们需要一个页面布局,其中各个块将动态地调整自己的大小以适应其内容。我花了几天时间试图让它与CSS和div跨浏览器工作,这是一个完全的噩梦。我们换了桌子,一切都很顺利。

然而,我们的产品有一个非常封闭的受众(我们销售的是带有web界面的硬件),可访问性问题不是我们关心的问题。我不知道为什么屏幕阅读器不能很好地处理表格,但我猜如果这是开发人员必须处理的方式。