private void ShowVendors() { SupplierTransaction vendor = new SupplierTransaction(); DataTable dtOneTimeSuppliers = vendor.GetOneTimeSuppliers(connstring, hdnCategoryId.Value.Trim()); ddlVendorName.DataSource = dtOneTimeSuppliers; ddlVendorName.DataTextField = "VendorName"; ddlVendorName.DataValueField = "VendorId"; ddlVendorName.DataBind(); ddlVendorName.Items.Insert(0, ""); }