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Nested repeater will not display bound information from list

I am trying to get a page to display information in a row layout using repeaters. I have one working that allows me to dynamically create hyperlinks, however i cant get my nested repeater to work to display the date the file was created. Is it possible to use repeaters to dynamically display multiple variables from lists as i'm trying to do below?
.aspx
<asp:Repeater id="repLinks" runat="server">
<ItemTemplate>
<tr><td>
<asp:HyperLink runat="server" NavigateUrl='<%# Container.DataItem.ToString() %>' Text="<%# Container.DataItem.ToString().Split('\\').Last() %>" />
<td>
<asp:Repeater ID="Repeater2" runat="server" OnItemDataBound="Repeater2_ItemDataBound" >
<ItemTemplate>
<%# Container.DataItem.ToString()%>
</ItemTemplate>
</asp:Repeater>
</td>
<td>
Submitted By <!--add repeater-->
</td>
<td>
Mark as Billed <!--add repeater-->
</td>
</td></tr>
</ItemTemplate>
</asp:Repeater>
.aspx.cs
public List<string> CD = new List<string>();
protected void Page_Load(object sender, EventArgs e)
{
//Welcomes User
string Uname = Environment.UserName;
UserName.Font.Size = 17;
UserName.Text = "Welcome: " + Uname;
//gives path and constructs lists for directory paths and file links
string root = "C:\\Users\\James\\Documents\\Visual Studio 2015\\WebSites";
List<string> lLinks = new List<string>();
//adds files to list
foreach (var path in Directory.GetDirectories(#root))
{
foreach (var path2 in Directory.GetFiles(path))
{
lLinks.Add(path2);
CD.Add(File.GetCreationTime(path2).Date.ToString("yyyy-mm-dd"));
}
}
//Define your list contents here
repLinks.DataSource = lLinks;
repLinks.DataBind();
}
protected void Repeater2_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
Repeater Repeater2 = (Repeater)(e.Item.FindControl("Repeater2"));
Repeater2.DataSource = CD;
Repeater2.DataBind();
}
}

The issue with your code is that you are binding the nested repeater control (Repeater2) in the ItemDataBound event of Repeater2 repeater itself which will never get fired because ItemDataBound event is fired for each item in collection when it is bounded to the repeater control.
You should write the logic in ItemDataBound event of your parent repeater like this:-
<asp:Repeater id="repLinks" runat="server" OnItemDataBound="Repeater1_ItemDataBound">
Then, write the logic in this event handler:-
protected void Repeater1_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item ||
e.Item.ItemType == ListItemType.AlternatingItem)
{
Repeater Repeater2 = (Repeater)(e.Item.FindControl("Repeater2"));
Repeater2.DataSource = CD;
Repeater2.DataBind();
}
}
Also, In the Page_Load event you should bind the Parent Repeater Repeater1 on just the initial page load so wrap it inside !IsPostBack and populate your datasource lLinks & CD from a separate method intead of doing it in Page_Load event.

How to access the current ItemType Item value from OnItemCommand method of ListView?

In aspx page:
<asp:ListView ID="ListViewPosts" ItemType="Post"
SelectMethod="ListViewPosts_GetData" runat="server"
OnItemCommand="Insert_Comment"
OnItemDataBound="ListViewPosts_ItemDataBound">
...
...
</asp:ListView>
Code behind:
protected void Insert_Comment(object sender, ListViewCommandEventArgs e)
{
...
Post p = Item; //where Item stands for the current Post record in ListView.
...
}
If I have this ListView where in ItemType="Post"; Post is a database table.
How to access the current value of Item (which stands for the current record from thePost table) in the code behind method Insert_Comment
I asked a question for OnItemDataBound method and the code:
Post p = e.Item.DataItem as Post works well. I tried the same code for OnItemCommand but the variable Post p gets null value!!.
I can use CommandArgument but I am wondering if I can get the Post item directly like the way I can with OnItemDataBound methos.

You can use use .DataItem only within OnItemDataBound. You may pass the Id of the Item and use it to bring the Item back from the database:
<asp:ListView ID="ListViewPosts" ItemType="Post"
SelectMethod="ListViewPosts_GetData" runat="server"
OnItemDataBound="ListViewPosts_ItemDataBound">
<ItemTemplate>
<asp:LinkButton runat="server" ID="btn_InsertComment" CommandName="Insert_Comment" CommandArgument='<%# Eval("PostID") %>' Text="Insert" />
</ItemTemplate>
</asp:ListView>
protected void Insert_Comment(object sender, ListViewCommandEventArgs e)
{
LinkButton btn_InsertComment = (LinkButton) sender;
string postId = btn_InsertComment.CommandArgument;
//use this id to create a new comment
}

Gridview rowdatabound error : Multiple controls with the same ID 'hlLink' were found. FindControl requires that controls have unique ID

I have a gridview that has link and description to be rendered on the page.
written the below code in gridview in .aspx
<Columns>
<asp:TemplateField>
<ItemTemplate>
<p>
<asp:HyperLink ID="hlLink" runat="server" Target="_self"></asp:HyperLink></p>
</ItemTemplate>
<ItemTemplate>
<p>
<asp:Literal ID="litSummary" runat="server"></asp:Literal></p>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<AlternatingItemTemplate>
<p>
<asp:HyperLink ID="hlLink" runat="server" Target="_self"></asp:HyperLink></p>
</AlternatingItemTemplate>
<AlternatingItemTemplate>
<p>
<asp:Literal ID="litSummary" runat="server"></asp:Literal></p>
</AlternatingItemTemplate>
</asp:TemplateField>
</Columns>
and below in .aspx.csin gridview rowdataboundevent
protected void gvResults_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
SearchResultItem data = (SearchResultItem)e.Row.DataItem;
HyperLink hlLink = (HyperLink)e.Row.FindControl("hlLink");
Literal litSummary = (Literal)e.Row.FindControl("litSummary");
if (data.Description != null)
{
hlLink.Text = data.Title;
hlLink.NavigateUrl = data.Path.Replace("&", "&");
litSummary.Text = data.Description;
}
else
{
hlLink.Text = data.Path;
hlLink.NavigateUrl = data.Path.Replace("&", "&");
litSummary.Text = data.Path;
}
}
here SearchResultItem: is the result item that has link and description details.
First time when row bound event is called, it binds the data correctly, second time when called throws error "Multiple controls with the same ID 'hlLink' were found. FindControl requires that controls have unique IDs.
Please let me know whats error with the code.
Thanks

Problem : you are trying to create the same controls with same ID multiple times.
Solution : you need to remove the controls before creating them.
Try This:
void RemoveControls()
{
HyperLink l1 = (HyperLink)Page.FindControl("hlLink");
Literal l2 = (Literal)Page.FindControl("litSummary");
if(l1!= null)
Page.Controls.Remove(l1);
if(l2!= null)
Page.Controls.Remove(l2);
}
Solution 2: Pagination for Repeater control.
for implementing pagination in Repeater control you need to create PagedDataSource.
Try This:
PagedDataSource pds = new PagedDataSource();
pds.DataSource = ds.Tables[0].DefaultView;
pds.AllowPaging = true;
pds.PageSize = 8;//page sizes

Repeater which Event to use to find a control inside the repeater

I use asp.net and c#4.
I have a repeater within inside a HyperLink Control.
I need to Find the HyperLink Control and change some of its properties with some logic before rendering it on the page.
With my code here posted I get a null value for the control so I'm not able to get it.
Any idea what I'm doing wrong? Thanks for your time on this.
<asp:Repeater ID="RepeaterEditorsChoice" runat="server" DataSourceID="ObjectDataSourceEditorsChoice"
OnItemCreated="RepeaterEditorsChoice_ItemCreated" OnItemDataBound="RepeaterEditorsChoice_ItemDataBound">
<HeaderTemplate>
<ul>
</HeaderTemplate>
<ItemTemplate>
<li>
<asp:HyperLink ID="uxLink" runat="server"></asp:HyperLink>
</li>
</ItemTemplate>
<FooterTemplate>
</ul>
</FooterTemplate>
</asp:Repeater>
CODE BEHIND:
protected void RepeaterEditorsChoice_ItemCreated(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.AlternatingItem || e.Item.ItemType == ListItemType.Item)
{
HyperLink myLink = (HyperLink)((Repeater)sender).FindControl("uxLInk"); // ERROR: it is null
dynamic o = e.Item.DataItem;
if (o.TypeContent == "AR")
{
myLink.Text = #"'<%# Eval(\""Title\"") %>'";
myLink.NavigateUrl = #"'<%# GetRouteUrl(""ArticleDetails"", new {ContentId = Eval(""ContentId""), TitleUrl = Eval(""TitleUrl"")}) %>'";
}
if (o.TypeContent == "BP")
{
myLink.Text = #"'<%# Eval(\""Title\"") %>'";
myLink.NavigateUrl = #"'<%# GetRouteUrl(""BlogPostDetails"", new {ContentId = Eval(""ContentId""), TitleUrl = Eval(""TitleUrl"")}) %>'";
}
}
}

On item data bound
then just (YourClass)e.Item.FindControl("its name");

define variable in repeater?

I like to handle and compare a lot of date times in my repeater even I have to work more than one time with the same.
It's a bit ugly, to cast everywhere the Eval("MyDate") like ((DateTime)Eval("MyDate")) to substract 2 datetimes or to compare it, even if you have to do this more than in one operation.
I thought of saving all the evals in a var at start of the repeater?
DateTime mydt1 = Eval("myDate");
DateTime mydt2 = Eval("mydate");
after that, it's easy to do any operations in the whole repeater. Hope you understand my idea. Is this possible? I tried short but everytime errors.
mydt1 - mydt2....
Thank you and best regards.

You could call a method on the code behind page from the repeater using the DateTimes as arguments. The casting logic can be done in the code behind if the goal it to create a cleaner looking aspx page.
Example ASPX:
<asp:Repeater ID="Repeater1" runat="server">
<ItemTemplate>
<asp:Literal
ID="Literal1"
runat="server"
Text='<%# DateFoo(Eval("myDate1"), Eval("myDate2")) %>' />
</ItemTemplate>
</asp:Repeater>
Example C# code behind:
protected string DateFoo(Object o1, Object o2)
{
DateTime? dt1 = o1 as DateTime?;
DateTime? dt2 = o2 as DateTime?;
// Do logic with DateTimes
return "string";
}

If you want to add more logic to your repeater I would suggest you move the binding logic to the code behind:
ASPX:
<asp:Repeater id="myRepeater" runat="server">
<ItemTemplate>
<asp:Literal id="myLiteral" runat="server" />
</ItemTemplate>
</asp:Repater>
CS:
protected override void OnInit(EventArgs e)
{
myRepeater.ItemDataBound += myRepeater_ItemDataBound;
base.OnInit(e);
}
void myRepeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
// this method will be invoked once for every item that is data bound
// this check makes sure you're not in a header or a footer
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
// this is the single item being data bound, for instance, a user, if
// the data source is a List<User>
User user = (User) e.Item.DataItem;
// e.Item is your item, here you can find the controls in your template
Literal myLiteral = (Literal) e.Item.FindControl("myLiteral");
myLiteral.Text = user.Username + ", " + user.LastLoginDate.ToShortDateString();
// you can add any amount of logic here
// if you need to use it, e.Item.ItemIndex will tell you what index you're at
}
}

I hate evals with a passion.
This is why I use this code to be rid of them forever and go back to strong typing:
public static class DataItemExtensions
{
public static T As<T>(this IDataItemContainer repeater) where T : class
{
return (T)repeater.DataItem;
}
public static dynamic AsDynamic(this IDataItemContainer repeater)
{
return repeater.DataItem;
}
}
Then use it like this:
<asp:Repeater runat="server" DataSource="<%# this.MyObjectCollection %>">
<ItemTemplate>
<%# Container.As<MyObject>().DateTime %>
</ItemTemplate>
</asp:Repeater>
Note that if you use the Datasource like I did, you need to use this.DataBind() on the page.