dropdown list 的 RequiredFieldValidator

来源：互联网发布：知乎庄雅婷编辑：程序博客网时间：2024/05/19 20:46

<asp:DropDownList ID="ddlSelectAccount" runat="server" CssClass="clsDropWidthLarge">
</asp:DropDownList><br /><br />
<asp:RequiredFieldValidator ID="rfvAccountFacility" runat="server" ControlToValidate="ddlSelectAccount"

CssClass="lblSystemWarning" ErrorMessage=" * required" InitialValue="-1"></asp:RequiredFieldValidator>

if (ddlSelectAccount.SelectedIndex < 1)
                {
                    DataTable dtSelectAccount = LMS.Data.Account.getAccountIndented(UserSession.AccessibleAccountId);
                    ddlSelectAccount.DataSource = dtSelectAccount;
                    ddlSelectAccount.DataTextField = "title";
                    ddlSelectAccount.DataValueField = "account_id";
                    ddlSelectAccount.DataBind();
                    ddlSelectAccount.Items.Insert(0, new ListItem("--Select--", "-1"));

                }
                rowSelectAccount.Visible = true;

asp.net页面上dropdownlist是否选择的验证

<asp:comparevalidator id="checknat_id" runat="server" Display="Dynamic" ControlToValidate="ddlnat_id" Type="String" ValueToCompare="0" Operator="NotEqual" ErrorMessage="請選擇交易國家" ></asp:comparevalidator>
注释：ValueToCompare在这里仅支持与dropdownlist的selectvalue匹配；不与selectindex或text匹配
当然这里需要设置ddlnat_id.add(new item("请选择","0")然后再加入其他下拉列表