private void dataSources_SelectedIndexChanged(object sender, EventArgs e)
 {
     dataSource = ((FormattedDataSource)dataSources.SelectedItem).DataSource;
     PopulateEvents();
 }
 private void dataSources_SelectedIndexChanged(object sender, EventArgs e)
 {
     dataSource = ((FormattedDataSource) dataSources.SelectedItem).DataSource;
       PopulateEvents();
 }