CheckboxColumn and checkboxOptions value change?

Question

Yii

In Gridview CheckboxColumn I do
'checkboxOptions' => function($data, $key, $index, $widget) {
return ["value" => $data->sender_id];
},
that is, I put the user ID in the value
and how can I get it now in javascript
$('#pm_tbl').yiiGridView('getSelectedRows')) gives out the column ID, although the user ID is in the value