为什么< p>标签包含< div>里面的标签?
据我所知,这是正确的:
As far as I know, this is right:
<div>
<p>some words</p>
</div>
但这是错误的:
<p>
<div>some words</div>
</p>
第一个可以通过 W3C验证器(XHTML 1.0),但第二个则不能.我知道没有人会像第二个那样编写代码.我只想知道为什么.
The first one can pass the W3C validator (XHTML 1.0), but the second can't. I know that nobody will write code like the second one. I just want know why.
那其他标签的收容关系又如何呢?
And what about other tags' containment relationship?
HTML规范是寻找允许的收容关系的权威之地.参见例如 http://www.w3.org/TR/html4/sgml/dtd.html .它指定哪些元素是块元素,哪些是内联元素.对于这些列表,搜索标记为"HTML内容模型"的部分.
An authoritative place to look for allowed containment relations is the HTML spec. See, for example, http://www.w3.org/TR/html4/sgml/dtd.html. It specifies which elements are block elements and which are inline. For those lists, search for the section marked "HTML content models".
对于P元素,它指定以下内容,这表明P元素只允许包含内联元素.
For the P element, it specifies the following, which indicates that P elements are only allowed to contain inline elements.
<!ELEMENT P - O (%inline;)* -- paragraph -->
这与 http://www一致. w3.org/TR/html401/struct/text.html#h-9.3.1 ,其中指出P元素不能包含块级元素(包括P本身)."
This is consistent with http://www.w3.org/TR/html401/struct/text.html#h-9.3.1, which says that the P element "cannot contain block-level elements (including P itself)."