(开发篇) 控件研究~ 下拉列表中添加一条默认的选项 "请选择"

界面上的内容

1         <asp:DropDownList ID="company" runat="server" AppendDataBoundItems=true>
2             <asp:ListItem Selected="true">-请选择-</asp:ListItem>
3         </asp:DropDownList>

后台代码

1         for (int i = company.Items.Count - 1; i > 0; i--)
2         {
3             company.Items.RemoveAt(i);
4         }
5         this.company.DataSource = ds_company;
6         this.company.DataValueField = "department_no";
7         this.company.DataTextField = "department_name";
8         this.company.DataBind();

解析:

　　1.下拉列表中要添加 AppendDataBoundItems=true 属性

或者：　

            this.company.DataSource = ds_company;
            this.company.DataValueField = "department_no";
            this.company.DataTextField = "department_name";
            this.company.DataBind();

            this.company.Items.Add(new ListItem("请选择", "000000000"));
            this.company.SelectedValue = "000000000";