How to refresh FormDataSource in class.

void refreshCaller()
{
common common;
formDatasource common_ds;
;
common = element.args().record();
if (common.RecId)
{
if (common.isFormDataSource())
{
common_ds = common.datasource();
if (common_ds)
{
common_ds.reread();
common_ds.refresh();
}
}
}
}