Is it valid HTML to insert a hidden input between table rows?

Background: I am writing a Java app which auto generates a HTML table. As well 开发者_如何学Cas adding table rows, this app may insert hidden inputs. However, at present it simply inserts them into the table at the next opportunity, for example:

<table>
    <tr> ... </tr>
    <input type="hidden" />
    <tr> ... </tr>
</table>

So, my question: Is it valid HTML to insert a hidden input between rows like this, or is this likely to cause problems?

It's not valid.

<!ELEMENT TABLE - -
     (CAPTION?, (COL*|COLGROUP*), THEAD?, TFOOT?, TBODY+)>

No, it's not.

You should use the W3C validator and check by yourself your webpages : http://validator.w3.org/.

It's not valid.

From http://validator.w3.org/

Line 9, Column 27: document type does not allow element "input" here

It's not valid, after closing </tr> tag it can have only <tr> or </tbody> or </table>. If you test it with w3c validator It will fail.