private void invoiceDateComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
///Disable other drop down menu's if this is selected
if (invoiceDateComboBox.IsEnabled)
{
invoiceIDComboBox.IsEnabled = false;
invoiceAmountComboBox.IsEnabled = false;
}
///The two other drop down menu's will be disabled when this is being used
///When selected, this combo box will show a drop down list with invoice Dates
///The user will be able to highlight/select a date and it will be recieved
///by the dataGrid1 to show that specific invoice only
///
Console.Write("textbox Value: " + invoiceDateComboBox.SelectedItem);
//get query needed find invoice
String sQuery = mydb.SelectInvoiceDate(invoiceDateComboBox.SelectedItem.ToString());
//datatable used to fget table data.
dt = db.FillSqlDataTable(sQuery);
//fill the datagrid
invoiceGrid1.ItemsSource = dt.DefaultView;
}