datalist中根据条件判断颜色交替
我在datalist中以日期/主题的形式显示列表，其中如果日期相同则隐藏日期，最后的形式是
日期1
主题1（白）
主题2（灰）
主题3（白）
日期2
主题4（白）
主题5（灰）
...
我用了以下一段代码：
Private LastDate As DateTime = DateTime.Now.AddYears(-100)
Protected Sub DataList1_ItemDataBound(sender As Object, e As DataListItemEventArgs)
If e.Item.ItemType = ListItemType.AlternatingItem Or e.Item.ItemType = ListItemType.Item Then
Dim riqi As DateTime = DirectCast(DataBinder.Eval(e.Item.DataItem, "riqi"), DateTime)
If LastDate = riqi Then
Dim Panel1 As Panel = TryCast(e.Item.FindControl("Panel1"), Panel)
Panel1.Visible = False
End If
LastDate = riqi
End If
End Sub
<asp:DataList ID="DataList1" runat="server" RepeatColumns="1" RepeatDirection="Vertical"
RepeatLayout="Flow" OnItemDataBound="DataList1_ItemDataBound">
<ItemTemplate>
<asp:Panel ID="Panel1" runat="server">
<%# Eval("riqi")%><br>
</asp:Panel>
<%# Eval("zhuti")%><br>
<br>
</ItemTemplate>
</asp:DataList>
可以达到我希望的效果，现在的问题是，怎样设置颜色交替？即从每个日期开始交替颜色，而不是从主题1开始交替颜色，否则主题4的那一行就成了灰色。请各位朋友帮忙看看！谢谢！
[解决办法]
你可以这样
<%@ Page Language="VB" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><script runat="server"> Protected Sub Page_Load(sender As Object, e As EventArgs) If Not Page.IsPostBack Then Dim ds As New System.Data.DataSet() Dim dataTable1 As New System.Data.DataTable("BlogUser") Dim dr As System.Data.DataRow dataTable1.Columns.Add(New System.Data.DataColumn("UserId", GetType(System.Int32))) dataTable1.Columns.Add(New System.Data.DataColumn("UserName", GetType(System.String))) dataTable1.Columns.Add(New System.Data.DataColumn("riqi", GetType(System.DateTime))) dr = dataTable1.Rows.Add(New [Object]() {1, "【孟子E章】" + 1.ToString(), DateTime.ParseExact("2011-12-12", "yyyy-MM-dd", Nothing)}) dr = dataTable1.Rows.Add(New [Object]() {2, "【孟子E章】" + 2.ToString(), DateTime.ParseExact("2011-12-12", "yyyy-MM-dd", Nothing)}) dr = dataTable1.Rows.Add(New [Object]() {3, "【孟子E章】" + 3.ToString(), DateTime.ParseExact("2012-12-11", "yyyy-MM-dd", Nothing)}) dr = dataTable1.Rows.Add(New [Object]() {4, "【孟子E章】" + 4.ToString(), DateTime.ParseExact("2012-12-11", "yyyy-MM-dd", Nothing)}) dr = dataTable1.Rows.Add(New [Object]() {5, "【孟子E章】" + 5.ToString(), DateTime.ParseExact("2012-12-11", "yyyy-MM-dd", Nothing)}) DataList1.DataSource = dataTable1 DataList1.DataBind() End If End Sub Private LastDate As DateTime = DateTime.Now.AddYears(-100) Protected Sub DataList1_ItemDataBound(sender As Object, e As DataListItemEventArgs) If e.Item.ItemType = ListItemType.AlternatingItem Or e.Item.ItemType = ListItemType.Item Then Dim riqi As DateTime = DirectCast(DataBinder.Eval(e.Item.DataItem, "riqi"), DateTime) If LastDate = riqi Then Dim Panel1 As Panel = TryCast(e.Item.FindControl("Panel1"), Panel) Panel1.Visible = False End If Dim Panel2 As Panel = TryCast(e.Item.FindControl("Panel2"), Panel) If e.Item.ItemIndex Mod 2 = 0 Then Panel2.ForeColor = Drawing.ColorTranslator.FromHtml("#FFFFFF") Else Panel2.ForeColor = Drawing.ColorTranslator.FromHtml("#EEEEEE") End If LastDate = riqi End If End Sub</script><html xmlns="http://www.w3.org/1999/xhtml"><head id="Head1" runat="server"> <title></title></head><body style="background:pink"> <form id="form1" runat="server"> <asp:DataList ID="DataList1" runat="server" RepeatColumns="1" RepeatDirection="Vertical" RepeatLayout="Flow" OnItemDataBound="DataList1_ItemDataBound"> <ItemTemplate> <asp:Panel ID="Panel1" runat="server"> <%# Eval("riqi")%> </asp:Panel> <asp:Panel ID="Panel2" runat="server"><%# Eval("UserName")%></asp:Panel> </ItemTemplate> </asp:DataList> </form></body></html