<?php
 
$fields = array('data1', 'data2', 'data3', 'data4', 'data5');
$form = "";
$form .= '<form>' . "\n";
 
$count = 0;
foreach ($fields as $f) {
 
   // open .form-group and .row every two loops?
   if($count % 2 == 0) $form .='<div class="form-group"><div class="row">' . "\n";
   $form .= '  <div class="col-sm-6">'; // always open column
 
   $form .= $f;
 
   $form .= '</div>' . "\n"; // always close column
 
   // close .form-group and .row every two loops?
   if($count % 2 != 0) $form .= '</div></div>';
 
   $count++;
}
 
if ($count %2 != 0) {
	// close last DIV if an odd number of fields
	$form .= '</div></div>';
}
 
 
$form .= "\n" . '</form>';
echo $form;

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