问题
While target="_blank" is deprecated, why is the W3C validator not giving an error about this ? You can paste and check this code int the validator:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>
<body>
<p>
<a href="http://www.stackoverflow.com" title="New window will open" target="_blank">Link opens in new window</a>
</p>
</body>
</html>
Edit:
Does it mean that XHTML 1.1 supports target=”_blank”, but XHTML 1.0 strict does not? Or is it a bug in the W3C validator?
回答1:
You are being validated as XHTML Transitional rather than Strict. If you manually override the doctype to XHTML 1.0 Strict you get this error:
Error Line 11, Column 76: Attribute "target" exists, but can not be used for this element.
…om" title="New window will open" target="_blank">Link opens in new window
Use this doctype if you want to be strict:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
The transitional schemas still allow certain deprecated elements and attributes, I guess to help people transition in steps towards a stricter markup.
EDIT:
OK, so the original code was XHTML 1.1 of which there is just one single version (no Strict/Transitional), and according this FAQ the target attribute is indeed not allowed. So I guess this must be a bug in the validator.
回答2:
It is deprecated but not removed. That's why i think there is problem in validating that.
回答3:
The XHTML1.1 documentation shows that the target attribute of an a element can be "anything".
回答4:
Does it means XHTML 1.1 support target=”_blank” but XHTML 1.0 strict not?
Well, Yes.
If you need a workaround for your problem, then this is one of them. Another option is to use window.open() instead of target="_blank".
回答5:
I used your code and I got the following error.
Error found while checking this document as XHTML 1.1!
Validation Output: 1 Error
Error Line 11, Column 76: there is no attribute "target"
….com" title="New window will open" target="_blank">Link opens in new window
The validator is working as of 1/30/2012. You cannot pass validation using target="_blank"
Replace with this valid portion of code:
onclick="target='_blank';"
回答6:
While xhtml may support "targrt="_blank", it WILL NOT validate it because it hase been depreciated. If you don't want to use JS, you will have to use transitional instead of strict in your "document type".
来源：https://stackoverflow.com/questions/1914143/why-isnt-my-document-validating-as-xhtml-1-1-strict