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How to access control inside parent control? (asp.net c#)

I have page with listview in it. There is label and dropdownlist in listview. I would like to access the text of label from ddlTags_Init() method.
Code:
<asp:ListView ID="ListView1" runat="server" DataSourceID="SqlDataSource1"
DataKeyNames="id_Image" onitemdatabound="ListView1_ItemDataBound">
<ItemTemplate>
<asp:Label ID="TagsLabel" runat="server" Text='<%# Eval("Tags") %>' />
<asp:DropDownList ID="ddlTags" runat="server" OnInit="ddlTags_Init" >
</asp:DropDownList>
</ItemTemplate>
</asp:ListView>
Code behind:
protected void ddlTags_Init(object sender, EventArgs e)
{
DropDownList ddlTags = (DropDownList)sender;
Label lblTag = (Label)ddlTags.Parent.FindControl("TagsLabel");
string text=lblTag.Text;
}
At the moment i am stuck with
Label lblTag = (Label)ddlTags.Parent.FindControl("TagsLabel");
Anyone knows what am i missing?
Thanks, Jim

Assuming that there are more than 1 elements in the listview datasource, why don't you put your code in the ItemDataBound handler? I think that it should work.

Init is too early to get the bind value of Label. In other words, label value hasn't been bind yet.
Instead you might want to consider using ItemDataBound method.
<asp:ListView ID="ListView1" runat="server"
OnItemDataBound="ListView1_ItemDataBound" ...>
....
</asp:ListView>
protected void ListView1_ItemDataBound(object sender, ListViewItemEventArgs e)
{
if (e.Item.ItemType == ListViewItemType.DataItem)
{
var ddlTags = e.Item.FindControl("ddlTags") as DropDownList;
var tagsLabel = e.Item.FindControl("TagsLabel") as Label;
}
}

ASP.NET Button OnClick within Repeater and LoginView

I'm developing a ASP.NET website with a C# backend. I'm having a problem with how to set an onclick event for buttons that are nested inside of both a loginview and a repeater. The code works fine for displaying all of the other data (anonymous view displays only an error message) but right now the buttons just redirect to the same page and remove the repeater and all contents, whereas they're supposed to run a specific delete function. The repeater, as it is right now, uses an alternatingitem template. If I remove the buttons from the nested controls, they work. I've tried this with buttons, linkbuttons, and imagebuttons. I'd rather use the latter, if possible. Is it possible to assign an Onclick to these buttons if they're nested like this? If not, what approach should I use?
<asp:LoginView ID="LoginLinksView" runat="server" EnableViewState="false">
<AnonymousTemplate>
<asp:Label ID="errorlabel" runat="server"></asp:Label>
</AnonymousTemplate>
<LoggedInTemplate>
<asp:Repeater id="Repeater" runat="server" >
<HeaderTemplate>
<table cellspacing="0" cellpadding="0">
<thead></thead>
</HeaderTemplate>
<ItemTemplate>
<tr class="Repeaterrow">
<!--Additional code here-->
<asp:ImageButton ID="delbutton" runat="server" ImageUrl=
"~/Images/delete.png" Onclick="DeleteOnClick"/>
</tr>
</ItemTemplate>
<AlternatingItemTemplate>
<tr class="Repeaterrow">
<!--Additional code here-->
<asp:ImageButton ID="delbutton" runat="server" ImageUrl=
"~/Images/delete.png" Onclick="DeleteOnClick"/>
</tr>
</AlternatingItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>
</LoggedInTemplate>
</asp:LoginView>

Here are the problems with your approach
1- The button issues postback as it should. But you need to put some CommandArgument with to identify "key" or which row you are processing it for.
2- Re Bind your Repeater with source. Below is the sample code for you.
protected void Page_Load(object sender, EventArgs e)
{
BindRepeater();
}
private void BindRepeater()
{
List<int> items = new List<int>();
for (int i = 0; i < 10; i++)
{
items.Add(i);
}
Repeater.DataSource = items;
Repeater.DataBind();
}
protected void DeleteOnClick(object sender, EventArgs e)
{
ImageButton delbutton = (sender as ImageButton);
//1- call your method with passing in delbutton.CommandArgument - it will give you key/ whatever you like
//2- Rebind the Repeater here and that will bind controls again...
BindRepeater();
}
protected void Repeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
ImageButton delbutton = (sender as RepeaterItem).FindControl("delbutton") as ImageButton;
if (delbutton != null)
{
delbutton.CommandArgument = (sender as RepeaterItem).ItemIndex.ToString();
}
}
and ASPX Repeater definition would change to
Thanks,
Riz

Getting control value when switching a view as part of a multiview

I have the following code in my aspx page:
<asp:Button id="display_button" runat="server" Text="Display" OnClick="Button1_Click" />
<asp:Button id="edit_button" runat="server" Text="Edit" OnClick="Button2_Click" />
<asp:Button id="save_button" runat="server" Text="Save" OnClick="Button3_Click" Visible="false" />
<asp:MultiView id="MultiView1" runat="server" ActiveViewIndex="0">
<asp:View id="View1" runat="server">
<asp:FormView id="view_program" runat="server">
<ItemTemplate>
<%# Eval("status").ToString().Trim() %>
</ItemTemplate>
</asp:FormView>
</asp:View>
<asp:View id="View2" runat="server">
<asp:FormView id="edit_program" runat="server">
<ItemTemplate>
<asp:DropDownList id="p_status" runat="server">
</asp:DropDownList>
</ItemTemplate>
</asp:FormView>
</asp:View>
</asp:MultiView>
and the following functions attached to the buttons in the code-behind page:
protected void Button1_Click(object sender, EventArgs e)
{
MultiView1.SetActiveView(View1);
save_button.Visible = false;
}
protected void Button2_Click(object sender, EventArgs e)
{
MultiView1.SetActiveView(View2);
save_button.Visible = true;
}
protected void Button3_Click(object sender, EventArgs e)
{
DropDownList p_status = edit_program.FindControl("p_status") as DropDownList;
var status = p_status.SelectedValue;
Label1.Text = status;
//save_button.Visible = false;
//MultiView1.SetActiveView(View1);
}
The idea being, that there are two views, the first displays the information, if the user wants to edit the information, they click button 2 which changes the view to the edit mode, which has the controls (drop downs, text fields, etc). It also makes the 'save' button appear.
What I am trying to make happen is, when the save button is clicked, it will grab all of the values from the various fields, update the object and then update the database. Then it would flip back to view1 with the updated info.
Problem is, as you can see in void Button3_Click, I try grab the values from the control, p_status, but it only gets the original value. example, the menu has three values, 'Green', 'Yellow', and 'Red'. Green is the default value and is selected when view2 is displayed. However, if I select Yellow or Red, and click save, rather than the label being updated to display one of those two values, it always displays Green.
Any ideas?
edit: page load function per request below
protected void Page_Load(object sender, EventArgs e)
{
try
{
Person myPerson = new Person(userid);
TestProgram myProgram = new TestProgram(id);
List<TestProgram> program = new List<TestProgram> { myProgram };
view_program.DataSource = program;
view_program.DataBind();
edit_program.DataSource = program;
edit_program.DataBind();
DropDownList p_status = edit_program.FindControl("p_status") as DropDownList;
p_status.Items.Add(new ListItem("Green", "Green"));
p_status.Items.Add(new ListItem("Yellow", "Yellow"));
p_status.Items.Add(new ListItem("Red", "Red"));
//myProgram.Status = "Red";
p_status.SelectedValue = myProgram.Status;
}
catch (Exception ex)
{
Response.Write(ex);
Label1.Text = ex.ToString();
}
}

Whoops...missed a little someting.. my
bad
when asp.net is not behaving as expected this is your best friend: MSDN: ASP.NET PAGE LIFECYLE
Upon Further Review...
there are a couple of problems here. your drop down list control with an id of "p_status" is contained inside a multiview (I forgot about what that meant...) you need to move the code to populate p_status into pre-render after checking to see if Multiveiw1.ActiveView = View2. Since it will always be a post back you need to bind values late in the page cycle

Can't find control within asp.net repeater?

I have the following repeater below and I am trying to find lblA in code behind and it fails. Below the markup are the attempts I have made:
<asp:Repeater ID="rptDetails" runat="server">
<HeaderTemplate>
<table>
</HeaderTemplate>
<ItemTemplate>
<tr>
<td><strong>A:</strong></td>
<td><asp:Label ID="lblA" runat="server"></asp:Label>
</td>
</tr>
</ItemTemplate>
</asp:Repeater>
</table>
First I tried,
Label lblA = (Label)rptDetails.FindControl("lblA");
but lblA was null
Then I tried,
Label lblA = (Label)rptDetails.Items[0].FindControl("lblA");
but Items was 0 even though m repeater contains 1 itemtemplate

You need to set the attribute OnItemDataBound="myFunction"
And then in your code do the following
void myFunction(object sender, RepeaterItemEventArgs e)
{
Label lblA = (Label)e.Item.FindControl("lblA");
}
Incidentally you can use this exact same approach for nested repeaters. IE:
<asp:Repeater ID="outerRepeater" runat="server" OnItemDataBound="outerFunction">
<ItemTemplate>
<asp:Repeater ID="innerRepeater" runat="server" OnItemDataBound="innerFunction">
<ItemTemplate><asp:Label ID="myLabel" runat="server" /></ItemTemplate>
</asp:Repeater>
</ItemTemplate>
</asp:Repeater>
And then in your code:
void outerFunction(object sender, RepeaterItemEventArgs e)
{
Repeater innerRepeater = (Repeater)e.Item.FindControl("innerRepeater");
innerRepeater.DataSource = ... // Some data source
innerRepeater.DataBind();
}
void innerFunction(object sender, RepeaterItemEventArgs e)
{
Label myLabel = (Label)e.Item.FindControl("myLabel");
}
All too often I see people manually binding items on an inner repeater and they don't realize how difficult they're making things for themselves.

I just had the same problem.
We are missing the item type while looping in the items. The very first item in the repeater is the header, and header does not have the asp elements we are looking for.
Try this:
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{Label lblA = (Label)rptDetails.Items[0].FindControl("lblA");}

Code for VB.net
Protected Sub rptDetails_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.RepeaterItemEventArgs) Handles rptDetails.ItemDataBound
If e.Item.ItemType = ListItemType.AlternatingItem Or e.Item.ItemType = ListItemType.Item Then
Dim lblA As Label = CType(e.Item.FindControl("lblA"), Label)
lblA.Text = "Found it!"
End If
End Sub

Investigate the Repeater.ItemDataBound Event.

You should bind first.
for example)
rptDetails.DataSource = dataSet.Tables["Order"];
rptDetails.DataBind();

How to pass in runtime a index of row for ListView?

I have an question, On my page i have a ListView control, I also have a button that has CommandArgument. I know i can read and find a control in the ListView as :
ListView.Items[i].FindControl("controlname");
and my button in ListView is like that
asp:Button ID="WisdomButton" runat="server" CommandName="UpdateWisdom" CommandArgument='<%# need my index for Item[i] to post here %>'
OnCommand="UpdateWisdom" Text="Update" />
I want to add index value in runtime to the CommantParameter, so when i go to the Function onCommand i will know exactly from what row[i] i Need to get my controls from ListView.
So my question is, how do i dinamicly add index of ListView.Rows[i] into CommmandArgument for the Button in runtime ?
Thanks in advance.

Check out the API
http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.listviewcommandeventargs.aspx
The ListViewCommandEventArgs item has an index, IE it is already available in the argument
ListViewDataItem dataItem = (ListViewDataItem)e.Item;
int i = dataItem.DisplayIndex;
But from here you will have access to those controls
e.Item.FindConrol("controlName");
If you are calling the method a different way you could aways assign the index through an ItemDataBound Event
void MyListView_ItemDataBound(object sender, ListViewItemEventArgs e)
{
((Button)e.Item.FindControl("WisdomButton")).CommandArgument = ((ListViewDataItem)e.Item).DisplayIndex;
}
OR try something like this for giggles
<asp:Button runat="server" CommandArgument='<%# DisplayIndex %>'/>
// OR
<asp:Button runat="server" CommandArgument='<%# NextIndex() %>'/>

It might help to know a little bit more about what your are trying to do. If your end goal is to get any of the properties from your bound object you can just cast the dataItem from the ListViewCommandEventArgs of the ItemCommand event. You don't need to retain the index or call FindControl at all.
Here is an example of how to get the bound Customer object.
ListView
<asp:ListView runat="server" id="Customers" ItemCommand="Customers_ItemCommand">
<LayoutTemplate>
<ul>
<asp:placeholder runat="server" id="itemPlaceholder" />
</ul>
</LayoutTemplate>
<ItemTemplate>
<li>
<asp:Button runat="server" id="Select" CommandName="Select" />
<%# Eval("Name")%>
</li>
</ItemTemplate>
</asp:ListView>
CodeBehind
public void Page_Load()
{
if (!Page.IsPostBack)
{
this.Customers.DataSource = GetCustomers();
this.Customers.DataBind();
}
}
public void Customers_ItemCommand(object sender, ListViewCommandEventArgs e)
{
if (e.CommandName == "Select")
{
if (e.Item.ItemType != ListViewItemType.DataItem)
return;
var customer = ((ListViewDataItem)e.Item).DataItem as Customer;
if (customer != null)
{
// Now work directly with the customer object.
Response.Redirect("viewCustomer.aspx?id=" + customer.Id);
}
}
}
Edit: In addtion when you cast the item to a ListViewDataItem, then you also expose a ((ListViewDataItem)e.Item).DataItemIndex property that might help you.