嵌套中继器-分组数据 [英] Nested repeaters - grouping data
问题描述
我从ASP.NET开始，我想知道是否存在任何智能"方式以分组形式显示DataTable中的数据?
想象下面的例子:我从SQL获取数据到已分组并排序的数据表:
I'm beginning with ASP.NET and I'm wondering, if there is any "smart" way of displaying data from DataTable in groups?
Imagine following example: I get data from SQL to datatable grouped and sorted alredy:
protected void Page_Load(object sender, EventArgs e)
{
DataTable dt = new DataTable();
dt.Columns.Add("parent", typeof(string));
dt.Columns.Add("child", typeof(string));
dt.Rows.Add("AAA", "111");
dt.Rows.Add("AAA", "222");
dt.Rows.Add("AAA", "333");
dt.Rows.Add("BBB", "444");
dt.Rows.Add("BBB", "555");
dt.Rows.Add("CCC", "666");
dt.Rows.Add("CCC", "777");
dt.Rows.Add("CCC", "888");
repeaterParent.DataSource = dt;
repeaterParent.DataBind();
}
，我想在下面的页面上显示它们:
and I want to display them on page like below:
我尝试为此使用嵌套中继器:
I've tried to use nested repeaters for that:
<asp:Repeater ID="repeaterParent" runat="server">
<ItemTemplate>
<b><%# DataBinder.Eval(Container.DataItem, "parent") %></b>
<br />
<asp:repeater id="repeaterChild" runat="server">
<itemtemplate>
- <%# DataBinder.Eval(Container.DataItem, "child") %> <br />
</itemtemplate>
</asp:repeater>
</ItemTemplate>
</asp:Repeater>
当然不起作用-结果如下-它既未分组也未显示子项:
Of course it doesn't work - the result is following - it's neither grouped nor a child is being displayed:
该怎么做-控件不必是重复器-它可以是列表视图，项目符号列表或类似的东西.
How can it be done - the control doesn't have to be repeater - it could be listview, bulleted list or something similar.
最好，如果有某种智能"方式-所以我只将数据表绑定到数据源，然后控件为我进行其余(分组)工作.我宁愿避免将数据源表拆分为两个不同的源，或者避免对每个父项进行SQL查询并使用ItemDataBound事件-只要有可能.如果不是，您可以向我展示任何方法吗?.NET版本:4.0
Best, if there's some "smart" way - so I just bind datatable to datasource, and the control makes the rest (grouping) for me. I would prefer to avoid splitting datasource table into two different sources or making SQL query for each parent item and playing with ItemDataBound event - as long as it's possible. If not - can you show me any way of doing that? .NET version: 4.0
最诚挚的问候，
马辛
Best regards,
Marcin
-
我找到了以下解决方案，但是，我真的不喜欢它，因为每个项目的源表过滤成本很高，我不确定它在大型源数据表中的表现如何.我将很高兴听到是否有更好的解决方案:
--
I've found following solution, however, I don't really like it because costly filtering source table for each item, I'm not sure how it will behave with large source datatable. I'll gladly hear if there's a better solution:
protected void repeaterParent_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
DataRowView drv = (DataRowView)e.Item.DataItem;
string parent = drv["parent"].ToString();
dt.DefaultView.RowFilter = string.Format("[parent]='{0}'", parent);
DataTable dtChild = dt.DefaultView.ToTable(true, "child");
Repeater repeaterChild = (Repeater)e.Item.FindControl("repeaterChild");
repeaterChild.DataSource = dtChild;
repeaterChild.DataBind();
}
推荐答案
您处在正确的轨道上，但是您只有一个数据源，这是第一个转发器的输入.
You are on the right track, but ou have only one datasource and that is the input for the first repeater.
您需要向第二个(嵌套的)中继器添加第二个数据源.例如，一个函数返回第一个数据源中实际父级的子级.
You need to add a second datasource to the second (nested) repeater. For example a function that returns the childs of the actual parent in the first datasource.
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