Question

我无法更改当前学年的选定值我使用下面的代码：

Asp.net

    <table>
    <tr>
    <td>
    <b><asp:Label ID="lblSelectAcYear" runat="server" Text="Select AcYear"></asp:Label></b>
    </td>
    <td>
    <asp:DropDownList ID="ddlAcYear" runat="server" OnDataBinding="ddlBinding" OnDataBound="ddlAcYear_DataBound" AutoPostBack="true" Width="150px" OnSelectedIndexChanged="ddlAcYear_SelectedIndexChanged">

    </asp:DropDownList>
    </td>
    <td><b><asp:Label ID="lblSelectSem" runat="server" Text="Select Semester"></asp:Label></b></td>
    <td>
    <asp:RadioButtonList ID="rblSelectSem" runat="server" AutoPostBack="true" RepeatDirection="Horizontal">
    <asp:ListItem Enabled="true" Selected="True" Text="Even"></asp:ListItem>
    <asp:ListItem Enabled="true" Text="Odd"></asp:ListItem>
    </asp:RadioButtonList>
    </td>
    </tr>
    </table>

和背后的代码

        ddlAcYear.DataSource = Res.AllData;
            ddlAcYear.DataValueField = "AcYearId";

            ddlAcYear.DataTextField = "AcYear";
            ddlAcYear.DataBind();
            foreach (DataRow dr in Res.AllData.Rows)
            {
                if ((DateTime.Now.Date > Convert.ToDateTime(dr.ItemArray[2]).Date && DateTime.Now.Date < Convert.ToDateTime(dr.ItemArray[3]).Date))
                {

                    ddlAcYear.SelectedValue = dr.ItemArray[0].ToString();



                }

            }

当我调试时，所选值显示正确，但是当显示页面时，会显示下拉列表中的第一项。：'（

Answer 1

这是我总是在下拉列表中选择项目的方式：

 ListItem liId = ddlAcYear.Items.FindByValue(dr.ItemArray[0].ToString());
 if (liId != null) {
     liId.Selected = true;
 }

无法更改当前学年下拉列表中的选定值

1 个答案: