public FM_Overview()
{
InitializeComponent();
DataTable dt_invoice = sq.DataTable(FM_LoginScreen.conString, "InvoiceTable");
DataTable dt_client = sq.DataTable(FM_LoginScreen.conString, "ClientTable");
DataSet ds = new DataSet();
ds.Tables.Add(dt_invoice);
ds.Tables.Add(dt_client);
dg_invoice.DataSource = ds;
dg_invoice.DataMember = dt_invoice.TableName;
dg_invoice.Refresh();
dg_client.DataSource = ds;
dg_client.DataMember = dt_client.TableName;
dg_client.Refresh();
}