[TYPO3-dev] show info from flexform on FE

[Bas van der Togt]

hello list,

I build a flexform and now i want tot get the information from the 
flexform into the frontend.

This is working (but now i get the whole xml.):
$content.= $this->cObj->data['pi_flexform'];

I only want to show the info from the flexform.
So i tried this, but it's not working. Does anybody know why?
$content.= $this->pi_getFFvalue($this->cObj->data['pi_flexform'], 
'what_to_display', 'sDEF');

My XML:
<T3DataStructure>
  <meta>
        <langDisable>1</langDisable>
  </meta>
  <sheets>
   <sDEF>
    <ROOT>
     <TCEforms>
 
<sheetTitle>LLL:EXT:ef_cart/locallang_db.php:tt_content.pi_flexform.sheet_general</sheetTitle>
     </TCEforms>
     <type>array</type>
      <el>
       <what_to_display>
				<TCEforms>
				 
<label>LLL:EXT:ef_cart/locallang_db.php:tt_content.pi_flexform.what_to_display</label>
				  	<config>
				    	<type>select</type>
				      	<items type="array">
				        	<numIndex index="0" type="array">
				           	<numIndex index="0"></numIndex>
				           	<numIndex index="1"></numIndex>
				          </numIndex>
				          <numIndex index="1" type="array">
				           	<numIndex 
index="0">LLL:EXT:ef_cart/locallang_db.php:tt_content.pi_flexform.display_add</numIndex>
				           	<numIndex index="1">1</numIndex>
				           </numIndex>
				          <numIndex index="2" type="array">
				           	<numIndex 
index="0">LLL:EXT:ef_cart/locallang_db.php:tt_content.pi_flexform.display_list</numIndex>
				           	<numIndex index="1">2</numIndex>
				          </numIndex>
				          <numIndex index="3" type="array">
				           	<numIndex 
index="0">LLL:EXT:ef_cart/locallang_db.php:tt_content.pi_flexform.display_cart</numIndex>
				           	<numIndex index="1">3</numIndex>
				          </numIndex>
				      	</items>
				    	<minitems>0</minitems>
				    	<maxitems>1</maxitems>
				    	<size>1</size>
				  	</config>
					</TCEforms>
				</what_to_display>
      </el>
     </ROOT>
    </sDEF>
   </sheets>
</T3DataStructure>

Kind regards,
Bas