如何将另一项添加到绑定下拉列表
本文关键字:添加 一项 绑定 下拉列表 | 更新日期: 2023-09-27 18:15:10
我有一个DropDownList
控件在我的ASP。NET c# web应用程序,从SqlDataSource
读取。我有一个显示的项目列表,但我想在第一个项目中添加更多的文本,用value == 0
表示"请选择部门"。
下面是我的代码:
<asp:DropDownList
ID="DropDownList1"
DataSourceID="sdsdepartment"
runat="server"
DataTextField="department_name"
DataValueField="deptid"
></asp:DropDownList>
<asp:SqlDataSource
ID="sdsdepartment"
runat="server"
ConnectionString="<%$ ConnectionStrings:blabla %>"
SelectCommand="SELECT [department_name], [deptid] FROM [DEPARTMENT]"
></asp:SqlDataSource>
您可以将SelectCommand更改为:
SELECT 'Please select department' as [department_name], 0 as [deptid]
UNION
SELECT [department_name], [deptid] FROM [DEPARTMENT]
在Page_Load中添加以下行:
DropDownList1.Items。Insert(0, new ListItem("Please select department", "0"));
这很简单
<asp:DropDownList
ID="DropDownList1"
DataSourceID="sdsdepartment"
runat="server"
DataTextField="department_name"
DataValueField="deptid"
AppendDataBoundItems="True" // set this property to True
>
<asp:ListItem Text="select Department" Value="0"></asp:ListItem> //here add one default item
</asp:DropDownList>
<asp:SqlDataSource
ID="sdsdepartment"
runat="server"
ConnectionString="<%$ ConnectionStrings:blabla %>"SelectCommand="SELECT [department_name],
[deptid] FROM [DEPARTMENT]"
></asp:SqlDataSource>