[web2py] validate table cell

[Wouter Pronk]

Hello All,

I have a form that looks similar to this:
<form>
<table>
<tr><td><input name="N" value="123"/></td></tr>
<tr><td><input name="N" value=""/></td></tr>
</table>
<input type="submit">
</form>

On submit I would like web2py to validate all values for name="N" and if 
one is empty then give a response.flash like "line 2 is empty!".
How can I accomplish this?

Thanks, Wouter

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