我们可以有一个嵌套的html标签吗？

Question

I am parsing and html/xml file. I am bit confused with the fact that can we have a nested tag like this.

<A a="#" b="#".....<xyz>...</xyz> />

If yes can you please point out me the place where I could get information about this.

Answer 1

No you cannot. Other than the tag name and an optional closing ( /> ) the only thing allowed inside of the tag it self are attributes which take the form key=val . If you want to have < or > in a tag's attributes then they need to be encoded as < and >

Nested tags have to be done like so

<root>
   <child></child>
</root>

A tag that has a /> is called self closing, this means it has no children

Answer 2

It is not “well-formed XML,” ie XML at all. A tag cannot contain tags.

In HTML up to and including HTML 4.01, if parsed by the specifications (no browser does this), it would be somewhat different. A tag cannot contain a tag, but the < would implicitly close the a tag (tag, not element). There would still be an error due to lack of closing </a> tag. The characters /> would be taken as data characters, not markup.