在 ItemDataBound 事件处理程序中,您可以获得对 DropDownList 的引用并存储在成员变量中。您可以使用该变量来保留对后续 ItemDataBound 事件的 DropDownList 的访问。
听起来你需要做这样的事情:
public partial class _Default : System.Web.UI.Page
{
// Dummy data class. We'll bind a list of these to the repeater.
class File
{
public string Name { get; set; }
public int ID { get; set; }
public List<string> AListOfStrings { get; set; }
}
protected override void OnInit(EventArgs e)
{
base.OnInit(e);
rptrTest.ItemDataBound +=
new RepeaterItemEventHandler(rptrTest_ItemDataBound);
}
private DropDownList file1DropDown;
void rptrTest_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
// Find the DropDownList in the repeater's ItemTemplate
// so we can manipulate it.
DropDownList ddlSelect =
e.Item.FindControl("ddlSelect") as DropDownList;
File dataItem = (File)e.Item.DataItem;
DropDownList currentDropDownList;
switch (dataItem.ID)
{
case 1:
// Store the current item's DropDownList for later...
file1DropDown = ddlSelect;
currentDropDownList = file1DropDown;
break;
case 2:
case 3:
currentDropDownList = file1DropDown;
break;
default:
currentDropDownList = ddlSelect;
break;
}
// Get all of the strings starting with the current ID and
// add them to whichever DropDownList we need to modify.
currentDropDownList.Items.AddRange((
from s
in dataItem.AListOfStrings
where s.StartsWith(dataItem.ID.ToString())
select new ListItem(s)).ToArray());
}
protected void Page_Load(object sender, EventArgs e)
{
// Just build up a list of strings which we can filter later.
List<string> stringList = new List<string>();
foreach (string number in (new[] { "1", "2", "3", "4" }))
{
foreach (string letter in (new[] { "a", "b", "c", "d", "e" }))
{
stringList.Add(number + " " + letter);
}
}
List<File> myObjects = new List<File>(new[]
{
new File { ID = 1, Name = "Foo", AListOfStrings = stringList },
new File { ID = 2, Name = "Bar", AListOfStrings = stringList },
new File { ID = 3, Name = "Baz", AListOfStrings = stringList },
new File { ID = 4, Name = "Quux", AListOfStrings = stringList }
});
rptrTest.DataSource = myObjects;
rptrTest.DataBind();
}
}
...您的 ASPX 页面将包含一个看起来像这样的转发器:
<asp:Repeater runat="server" ID="rptrTest">
<ItemTemplate>
ID: <%#DataBinder.Eval(Container.DataItem, "ID")%>
<br />
Name: <%#DataBinder.Eval(Container.DataItem, "Name")%>
<br />
Select: <asp:DropDownList runat="server" ID="ddlSelect" />
<br /><br />
</ItemTemplate>
</asp:Repeater>
So in the rptrTest_ItemDataBound
event handler in the code-behind file, there's a switch statement that checks File.ID
to see which file instance it's binding to. If the ID is 1, the DropDownList gets assigned to file1DropDown
. Then on subsequent events, the logic inside the rest of the switch block decides which DropDownList we need to modify.