2 ways to do this.
1) without a placeholder (if using jquery)
# if you have a dropdown
<input type="radio" name="which_form" value="first">
<input type="radio" name="which_form" value="second">
# in jquery, say if input.which_form == first, then show first form. if input.which_form == second, then show second form. else show neither form
# that way you wouldnt have to do anything with eform. It would be based on jquery when the page is loaded. If the form doesnt validate, it will return the form with what was previously filled, so the radio will still be checked.
option 2)
function detectForm ( &$fields ) {
// set the placeholders
global $modx;
if ($fields[which_form]) == 'first' {
$output = '<style to hide here>;
} elseif ($fields[which_form == 'second') {
$output = '<style to hide here>';
} else {
$output = '<style to hide here>';
}
$modx->setPlaceholder('contactdisplaystatus',$output);
return true;
}
Then in your code, put the placeholder [+contactdisplaystatus+]. I think that should work, tho I think the jquery would be easiest.