DCA table field

In table with structure like this
$GLOBALS['TL_DCA']['']['fields'][''] = array(
'label' =>
'exclude' => true,
'inputType' => 'checkbox',
'options_callback' => array(),
'eval' => array(
mandatory => true;,
),
'save_callback' => array(),
),
'sql' => '',
);
How can i change 'mandatory' field if some cases are fulfilled. Like if this is 1 mandatory is true or 0 then is false?
Is possible to make some function to manage fields?
Thanks

You have to format your code to see your errors:

PHP Code:

---

$GLOBALS['TL_DCA']['']['fields'][''] = array(
  'label' =>
  'exclude' => true,
  'inputType' => 'checkbox',
  'options_callback' => array(),
  'eval' => array(
    mandatory => true;,
  ),
  'save_callback' => array(),
),
  'sql' => '',
); 


---

Corrected:

PHP Code:

---

$GLOBALS['TL_DCA']['TABLENAME']['fields']['FIELDNAME'] = array(
  'label'            => '',
  'exclude'          => true,
  'inputType'        => 'checkbox',
  'options_callback' => array(),
  'eval'             => array(
    'mandatory' => true
  ),
  'save_callback'    => array(),
  'sql'              => ''
); 


---

To just change the mandatory setting you have to use this:

PHP Code:

---

$GLOBALS['TL_DCA']['TABLENAME']['fields']['FIELDNAME']['eval']['mandatory'] = true; 


---

I deleted fields properties because of privacy. Thanks, your help saved my day. :)