Посмотрите на Mage_Adminhtml_Block_Widget_Grid::getCsv()
и Mage_Adminhtml_Block_Widget_Grid::getCsvFile()
в качестве примера.
Вот соответствующая часть первого в качестве примера (комментарии, добавленные мной).
public function getCsv()
{
$csv = '';
$this->_isExport = true;
$this->_prepareGrid(); // add the attributes to load, maybe required filters
$this->getCollection()->getSelect()->limit(); // only unique records
$this->getCollection()->setPageSize(0); // no paging, all records matching the set filters
$this->getCollection()->load();
$this->_afterLoadCollection(); // load additional data on the collection items if needed
$data = array();
// This foreach block adds headers to the columns
foreach ($this->_columns as $column) {
if (!$column->getIsSystem()) {
$data[] = '"'.$column->getExportHeader().'"';
}
}
$csv.= implode(',', $data)."\n";
// $column is an instance of Mage_Adminhtml_Block_Widget_Grid_Column
// Just a wrapper for getting the values from the collection items
foreach ($this->getCollection() as $item) {
$data = array();
foreach ($this->_columns as $column) {
if (!$column->getIsSystem()) {
$data[] = '"' . str_replace(array('"', '\\'), array('""', '\\\\'),
$column->getRowFieldExport($item)) . '"';
}
}
$csv.= implode(',', $data)."\n";
}
// Grid totals are only used by reports
if ($this->getCountTotals())
{
$data = array();
foreach ($this->_columns as $column) {
if (!$column->getIsSystem()) {
$data[] = '"' . str_replace(array('"', '\\'), array('""', '\\\\'),
$column->getRowFieldExport($this->getTotals())) . '"';
}
}
$csv.= implode(',', $data)."\n";
}
return $csv;
}