[TYPO3-english] set TCA userfunc to required

[Jochem Nabuurs]

Hi list,

For an extension I've built, I have used the TCA userfunc to create 
selectboxes with ajax functionality. I really like to make these boxes 
required, but because it's a userfunc I cannot seem to set 'eval' => 
'required', because 'eval' is then set as a parameter in the PA object.

I've tried adding the following code to the selectbox onchange method 
(found this by looking at the generated code for required input fields)

typo3form.fieldGet('data[tx_roqsmoelenboek_employee][1][voorletters]','required,trim','',0,'');TBE_EDITOR.fieldChanged('tx_roqsmo...

The 'required,trim' part is where I'm interested in. Normally, this is 
set through the 'eval' => ... option in TCA.


I hope somebody can explain to me how to make a required userfunc.

Thanks in advance!