转发器中的动态复选框列表，ASP.NET

Question

我在 Repeater 中有一个 CheckBoxList，我的代码来自这里 Dynamic dropdownlist in repeater, ASP.NET。

如果这样做：

<asp:CheckBoxList ID="chklWorkType" runat="server" OnDataBinding="chklWorkType_DataBinding"></asp:CheckBoxList>


protected void chklWorkType_DataBinding(object sender, System.EventArgs e)
{
    CheckBoxList chk = (CheckBoxList)(sender);

    chk.Items.Add(new ListItem("nem 1", "1"));
    chk.Items.Add(new ListItem("num 2", "2"));

    chk.SelectedValue = chk.DataValueField;
}

这是我的错误信息：

System.ArgumentOutOfRangeException: 'chklWorkType' has a SelectedValue which is invalid because it does not exist in the list of items.

Answer 1

DataValueField gets or sets the field of the data source that provides the value of each list item. So normally the name of a column or something like that. But you are using this name as SelectedValue 不存在，因为你没有分配一个，所以它是 String.Empty.

如果你想选择第一个项目，你可以使用这个：

chk.SelectedValue = "1";

这是第一个 ListItem(new ListItem("nem 1", "1")).

的值

当然你也可以使用 SelectedIndex:

chk.SelectedIndex = 0;

转发器中的动态复选框列表，ASP.NET

Dynamic Checkboxlist in repeater, ASP.NET

c#

asp.net

repeater

checkboxlist