=== doc_core_api === Ralf Hettinger, 08.08.2009: ''[TYPO3-core] RFC: Feature #7531: TCA displayCond - allow ANDed and/or ORed rulesets'':
Chapter: 4.2. $TCA array reference => ['columns'][fieldname] section , Key displayCond change Datatype to: string or array change Description: << Contains a condition rule for whether to display the field or not. >> Contains one rule or a ruleset of multiple rules for whether to display the field or not. One rule can be set as a string, multiple rules may be set as an array (see below). change Description (addition at the end): For passing multiple displayCond rules as a ruleset, they have to be grouped into an array with the keys AND and/or OR. Those keys are pointing to arrays, which contain elements being either strings (a single displayCond rule as described above) or arrays (again with keys being AND and/or OR and then containing another ruleset). Example: The following ruleset is true, if (my_field1 && my_field2!=3 && (my_field3 || my_field4 || my_field5 && my_field6) || my_field7 || my_field8) : [code] 'displayCond' => array ( 'AND' => array ( 'FIELD:my_field1:REQ:true', 'FIELD:my_field2:!=:3', 'OR' => array ( 'FIELD:my_field3:REQ:true', 'FIELD:my_field4:REQ:true', 'AND' => array( 'FIELD:my_field5:REQ:true', 'FIELD:my_field6:REQ:true', ) ) ), 'OR' => array ( 'FIELD:my_field7:REQ:true', 'FIELD:my_field8:REQ:true', ) ), [/code]