code/Forms/UploadField.php
public function getIsMultiUpload()
    {
        if (isset($this->multiUpload)) {
            return $this->multiUpload;
        }
        // Guess from record
        $record = $this->getRecord();
        $name = $this->getName();

        // Disabled for has_one components
        if ($record && DataObject::getSchema()->hasOneComponent(get_class($record), $name)) {
            return false;
        }
        return true;
    }
public function getIsMultiUpload()
    {
        if (isset($this->multiUpload)) {
            return $this->multiUpload;
        }
        // Guess from record
        $record = $this->getRecord();
        $name = $this->getName();

        // Disabled for has_one components
        if ($record && DataObject::getSchema()->hasOneComponent(get_class($record), $name)) {
            return false;
        }
        return true;
    }
public function getIsMultiUpload ( ) { if ( isset ( $ this -> multiUpload ) ) { return $ this -> multiUpload ; } // Guess from record $ record = $ this -> getRecord ( ) ; $ name = $ this -> getName ( ) ; // Disabled for has_one components if ( $ record && DataObject :: getSchema ( ) -> hasOneComponent ( get_class ( $ record ) , $ name ) ) { return false ; } return true ; }
Check if allowed to upload more than one file

@return bool
Check if allowed to upload more than one file