private void ComprobantesForm_Load(object sender, EventArgs e)
        {
            ComprobantesManager         comp     = new ComprobantesManager();
            ArticulosComprobanteManager detalles = new ArticulosComprobanteManager();

            metroComboBoxCentroCosto.DataSource    = comp.ListarCentroCosto();
            metroComboBoxCentroCosto.DisplayMember = "CentroCosto";
            metroComboBoxCentroCosto.ValueMember   = "IdCentroCosto";

            metroComboBoxContable.DataSource    = comp.ListarContable();
            metroComboBoxContable.DisplayMember = "Contable1";
            metroComboBoxContable.ValueMember   = "IdContable";

            metroComboBoxTipoFactura.DataSource    = comp.ListarTipoFactura();
            metroComboBoxTipoFactura.DisplayMember = "TipoFactura";
            metroComboBoxTipoFactura.ValueMember   = "IdTipoFactura";

            metroComboBoxCondicionCompra.DataSource    = comp.ListarCondicionCompra();
            metroComboBoxCondicionCompra.DisplayMember = "Condiciondecompra";
            metroComboBoxCondicionCompra.ValueMember   = "IdCondicionCompra";

            metroComboBoxTipoComprobante.DataSource    = comp.ListarTipoComprobantes();
            metroComboBoxTipoComprobante.DisplayMember = "TipoComprobante";
            metroComboBoxTipoComprobante.ValueMember   = "IdTipoComprobante";

            metroComboBoxMedioPago.DataSource    = comp.MediosdePago();
            metroComboBoxMedioPago.DisplayMember = "MediosPago1";
            metroComboBoxMedioPago.ValueMember   = "IdMedioPago";



            //autocomplete textbox con proveedores

            ProveedorManager p = new ProveedorManager();

            AutoCompleteStringCollection sourcename = new AutoCompleteStringCollection();

            sourcename.AddRange(p.listarNombreProveedores().ToArray());
            metroTextBoxProveedor.AutoCompleteMode         = AutoCompleteMode.Suggest;
            metroTextBoxProveedor.AutoCompleteSource       = AutoCompleteSource.CustomSource;
            metroTextBoxProveedor.AutoCompleteCustomSource = sourcename;
            //autocompletar combobox articulos

            ArticuloManager a = new ArticuloManager();
            AutoCompleteStringCollection sourcename2 = new AutoCompleteStringCollection();

            sourcename2.AddRange(a.ListarNombresArticulos().ToArray());
            this.metroTextBoxProducto.AutoCompleteMode         = AutoCompleteMode.Suggest;
            this.metroTextBoxProducto.AutoCompleteSource       = AutoCompleteSource.CustomSource;
            this.metroTextBoxProducto.AutoCompleteCustomSource = sourcename2;

            //deshabilitar paneles y botones
            metroPanelProducto.Enabled          = false;
            metroGridProductosServicios.Enabled = false;
            metroPanelGastos.Enabled            = false;
            metroPanelPago.Enabled       = false;
            metroButtonConfirmar.Enabled = false;
            metroButtonDescartar.Enabled = false;
        }