Develop Reference

Binding controls dynamically to PlaceHolder in asp:DataList

I can't seem to figure this one out but I'm trying to add a user control to a DataList at runtime (because the actual control type can differ). So if I hard code the control reference in the markup like this it works:
<asp:DataList ID="myDL" runat="server" RepeatDirection="Horizontal" RepeatColumns="3" OnItemDataBound="myDL_Item_Bound">
<ItemTemplate>
<prefix:MyControl ID="myControl1" runat="server" />
</ItemTemplate>
</asp:DataList>
But if I try to add it programmatically to a placeholder, it does not render the user controls (just empty td tags):
<asp:DataList ID="myDL" runat="server" RepeatDirection="Horizontal" RepeatColumns="3" OnItemDataBound="myDL_Item_Bound">
<ItemTemplate>
<asp:PlaceHolder ID="ph" runat="server">
</asp:PlaceHolder>
</ItemTemplate>
</asp:DataList>
protected void myDL_Item_Bound(Object sender, DataListItemEventArgs e) {
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem) {
PlaceHolder ph = (PlaceHolder)e.Item.FindControl("ph");
if (ph != null) {
MyControl ctrl = new MyControl();
ctrl.SomeProp = "xyz";
ph.Controls.Add(ctrl);
}
else {
MyControl ctrl = (MyControl)e.Item.FindControl("myControl1");
ctrl.SomeProp = "xyz";
}
}
}
what am I missing?

You are not adding the control to the page. You need to add it:
Control ctrl = (Control)Page.LoadControl("MyControl.ascx");
// MyControl ctrl = new MyControl();
ctrl.SomeProp = "xyz";
ph.Controls.Add(ctrl);

ASP.NET - Nested Repeaters

I have a repeater for different updates identified by "Update_ID". Each "Update_ID" has a number of images associated to it.
Therefore, I decided to nest a repeater for the images inside the repeater for updates.
The problem is that the image repeater never shows up, even if there is data to show.
Here is the code in ASP.NET:
<asp:Repeater ID="RepeaterUpdates" runat="server" onitemcommand="RepeaterUpdates_ItemCommand">
<ItemTemplate>
<div style="border: thin solid #808080">
<table id="TableUpdates_Repeater" runat="server" style="width:100%; margin:auto; background-image:url(Resources/Icons/white-background.gif)">
<tr>
<td style="width:25%">
<br />
<asp:Label ID="LabelUpdateID_Repeater" runat="server" Text="Update ID" Enabled="false"></asp:Label>
<asp:TextBox ID="TextBoxUpdateID_Repeater" runat="server" Width="50px" Text='<%# Eval("Update_ID") %>' Enabled="false"></asp:TextBox>
</td>
</tr>
</table>
<asp:Repeater ID="RepeaterImages" runat="server">
<ItemTemplate>
<label>Hello</label>
<asp:TextBox Text='<%# DataBinder.Eval(Container.DataItem,"Image_ID") %>' runat="server"></asp:TextBox>
</ItemTemplate>
</asp:Repeater>
</div>
</ItemTemplate>
</asp:Repeater>
Here is the code-behind:
protected void RepeaterUpdates_ItemCommand(object source, RepeaterCommandEventArgs e)
{
SqlConnection conn5 = new SqlConnection(connString);
SqlDataReader rdr5;
RepeaterItem item = e.Item;
TextBox Update_ID = (TextBox)item.FindControl("TextBoxUpdateID_Repeater");
try
{
conn5.Open();
SqlCommand cmd5 = new SqlCommand("SelectImages", conn5);
cmd5.CommandType = CommandType.StoredProcedure;
cmd5.Parameters.Add(new SqlParameter("#update_id", Update_ID.Text));
rdr5 = cmd5.ExecuteReader();
if ((item.ItemType == ListItemType.Item) || (item.ItemType == ListItemType.AlternatingItem))
{
Repeater ImageRepeater = (Repeater)item.FindControl("RepeaterImages");
ImageRepeater.DataSource = rdr5;
ImageRepeater.DataBind();
}
}
finally
{
conn5.Close();
}
}
As previously stated, the child repeater never shows up, even if there is data to display. How can I solve this problem please? Thanks

Rather than onitemcommand, call OnItemDataBound
Change RepeaterCommandEventArgs to RepeaterItemEventArgs

In addition to #Curt. Below is the code.
Code Behind
class Images
{
public int Image_ID;
}
protected void RepeaterUpdates_ItemCommand(object source, RepeaterCommandEventArgs e)
{
RepeaterItem item = e.Item;
TextBox Update_ID = (TextBox)item.FindControl("TextBoxUpdateID_Repeater");
try
{
conn5.Open();
using (SqlCommand cmd5 = new SqlCommand("SelectImages", conn5))
{
cmd5.CommandType = CommandType.StoredProcedure;
cmd5.Parameters.Add(new SqlParameter("#update_id", Update_ID.Text));
List<Images> Lst = new List<Images>();
using (SqlDataReader rdr5 = cmd5.ExecuteReader())
{
while (rdr5.Read())
{
Lst.Add(new Images { Image_ID = Convert.ToInt16(rdr5["Image_ID"]) });
}
if ((item.ItemType == ListItemType.Item) || (item.ItemType == ListItemType.AlternatingItem))
{
Repeater ImageRepeater = (Repeater)item.FindControl("RepeaterImages");
ImageRepeater.DataSource = Lst;
ImageRepeater.DataBind();
}
}
}
}
finally
{
conn5.Close();
}
}
HTML
You should Register ItemBoundData Event
<asp:Repeater ID="rp" runat="server" onitemdatabound="rp_ItemDataBound">
<ItemTemplate></ItemTemplate>
</asp:Repeater>
protected void rp_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
}

read textbox inside a repeater

I have 2 repeaters that print menu headers and menu items - on inside the other.
They look like this:
<asp:Repeater ID="ParentRepeater" runat="server" OnItemDataBound="ParentRepeater_ItemDataBound">
<ItemTemplate>
<h2>
<%#DataBinder.Eval(Container.DataItem, "typenavn") %></h2>
<asp:HiddenField ID="HiddenField1" Value='<%# Eval("id") %>' runat="server" />
<asp:Repeater ID="ChildRepeater" runat="server">
<ItemTemplate>
<table>
<tr>
<td style="width: 200px">
<%#DataBinder.Eval(Container.DataItem, "productName") %>
</td>
<td style="width: 200px">
<%#DataBinder.Eval(Container.DataItem, "pris") %>
</td>
<td>
<asp:HiddenField ID="HiddenField2" runat="server" />
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox><br />
</td>
</tr>
</table>
</ItemTemplate>
</asp:Repeater>
</ItemTemplate>
</asp:Repeater>
It's all good and fun and works.
But now I need to find the different textboxes - in the textboxes you can write how many of the different menu items you want.
I have tried many different things:
Control myControl1 = FindControl("MainContent_ParentRepeater_ChildRepeater_0_HB1_0");
And this:
foreach (RepeaterItem item in ParentRepeater.Items)
{
if (item.ItemType == ListItemType.Item)
{
TextBox txt = (TextBox)item.FindControl(("MainContent_ParentRepeater_ChildRepeater_0_HB1_0")) as TextBox;
// do something with "myTextBox.Text"
break;
}
}
And this:
foreach (RepeaterItem item1 in ParentRepeater.Items)
{
if (item1.ItemType == ListItemType.Item || item1.ItemType == ListItemType.AlternatingItem)
{
ChildRepeater = (Repeater)item1.FindControl("ChildRepeater");
foreach (RepeaterItem item2 in ChildRepeater.Items)
{
if (item2.ItemType == ListItemType.Item || item2.ItemType == ListItemType.AlternatingItem)
{
TextBox txt = (TextBox)item2.FindControl(("ct100$MainContent$ParentRepeater$ct100$ChildRepeater$ct100$HB1")) as TextBox; // MainContent_ParentRepeater_ChildRepeater_0_HB
}
}
}
break;
}
And none of it work. Can anybody out there help me?? How do I get hold of my textbox inside the repeater??

The FindControl function should take the ID of the server control, not the rendered client control. You should be able to do this:
var txt = item.FindControl("TextBox1") as TextBox;
if (txt != null)
{
// found it!
}
To adjust your code:
foreach (RepeaterItem item1 in ParentRepeater.Items)
{
if (item1.ItemType == ListItemType.Item || item1.ItemType == ListItemType.AlternatingItem)
{
ChildRepeater = (Repeater)item1.FindControl("ChildRepeater");
foreach (RepeaterItem item2 in ChildRepeater.Items)
{
if (item2.ItemType == ListItemType.Item || item2.ItemType == ListItemType.AlternatingItem)
{
TextBox txt = (TextBox)item2.FindControl(("TextBox1")) as TextBox;
}
}
}
}

First, you should use FindControl on the repeater you wish to locate a control within - for instance, ParentRepeater.FindControl("controlName") - as opposed to this.FindControl().
Secondly, you should use the ID of the control, not the Client ID - which is a different beast.

Repeater in ASP.net

I used repeater in asp.net. My problem is don't know how to hide a fields in repeater. There is a regular price and now price if regular price is equal to zero it will hide the fields and if not it will show the value of the regular price. i hope you can help on this.
here my code in asp:
<a href="<%=Utility.GetSiteRoot() %>/BookInfo.aspx?SKU=<%# Utility.SKUMask(Eval("lb_sku").ToString()) %>">
<img width="150px" src='<%# Eval("lb_picturepath")%>'>
</td>
<td valign="top">
<asp:Label ID="lb_titleLabel" runat="server" CssClass="center-head" Text='<%# Eval("lb_title") %>' />
<p><asp:Label ID="lb_descriptionLabel" runat="server" Text='<%# Eval("lb_description") %>' /></p>
<div class="price"><%# "Price: " + decimal.Round((decimal)Eval("lb_sellingprice"),2)%></div>
</td>
</tr>
<tr>
<td></td>
<td>
<a class="addtocart" href="<%=Utility.GetSiteRoot() %>/AddToCart.aspx?SKU=<%# Utility.SKUMask(Eval("lb_sku").ToString()) %>" >Add To Cart</a>
<a href="<%=Utility.GetSiteRoot() %>/BookInfo.aspx?SKU=<%# Utility.SKUMask(Eval("lb_sku").ToString()) %>" class="readmore">
View Details
</a></td>
thanks!

You would need to handle the OnItemDataBound event, and then change the visibility of the control. An example of this is shown below:
ASPX Page
<asp:Repeater ID="MyRepeater" OnItemDataBound="MyRepeater_OnItemDataBound" runat="server">
<ItemTemplate>
<asp:Label ID="RegularPriceLabel" runat="server" />
<br/>
<asp:Label ID="BuyNowPriceLabel" runat="server" />
</ItemTemplate>
</asp:Repeater>
Code Behind
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
MyRepeater.DataSource = GetDataSource();
MyRepeater.DataBind();
}
}
protected void MyRepeater_OnItemDataBound(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
// This will be your data object
MyEntity o = (MyEntity) e.Item.DataItem;
// Get the labels
Label RegularPriceLabel = (Label) e.Item.FindControl("RegularPriceLabel");
Label BuyNowPriceLabel = (Label) e.Item.FindControl("BuyNowPriceLabel");
// Only show regular price if it is set
RegularPriceLabel.Visible = (o.RegularPrice > 0);
// Populate labels
RegularPriceLabel.Text = o.RegularPrice.ToString();
BuyNowPriceLabel.Text = o.BuyNowPrice.ToString();
}
}

I would take a look at the ItemDataBound event of the Repeater. It will fire for every item in the repeater and allow you to do any code-behind (like hiding labels) more easily.
Edit: For your specific example, since you are formatting the price as well, it may be easier to just call a custom method to to render the price, like so:
ASPX:
<%#RenderPrice((decimal)Eval("lb_sellingprice"))%>
Method:
protected string RenderPrice(decimal price) {
if (price > 0) {
return "Price: $" + decimal.Round(price);
} else {
return string.Empty;
}
}
It's quick-and-dirty but it works.

Hide an element in ASP.net based on an if inside a Repeater

I know how to use a simple If statement wrapped in the <%# tags to hide something, but I don't know how to do it in a repeater when I need to access Container.DataItem, as in I need the dataItem currently being 'repeated'
eg
if (CurrentValidationMessage.Link != "")
{
show a hyperlink
}
Markup:
<asp:Repeater ID="repValidationResults" runat="server">
<HeaderTemplate>
</HeaderTemplate>
<ItemTemplate>
<a href='<%# ((MttImportValidationMessage)Container.DataItem).EditLink %>'> Link to erroneous Milestone </a>
<%# ((MttImportValidationMessage)Container.DataItem).Message %>
<br />
</ItemTemplate>
</asp:Repeater>

It might be more maintainable if you just tagged the controls in the repeater with id's and runat='server' and reference the DataItem in the ItemDataBound event by using e.Item.DataItem.
Then use e.Item.FindControl to reference your controls in the ItemTemplate and perform your logic.
protected void repeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.AlternatingItem || e.Item.ItemType == ListItemType.Item)
{
Domain.Employee employee = (Domain.Employee)e.Item.DataItem;
Control myControl = (Control)e.Item.FindControl("controlID");
//Perform logic
}
}

use ItemDataBound Event with repeater, and make the "a" tag with a runat="server" property and ID
protected void repValidationResults_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
RepeaterItem item = e.Item;
if (item.ItemType == ListItemType.AlternatingItem || item.ItemType == ListItemType.Item)
{
HyperLink link = (HyperLink) item.FindControl("link");
//Do all your logic here :)
}
}
MarkUp:
<asp:Repeater ID="repValidationResults" runat="server">
<HeaderTemplate>
</HeaderTemplate>
<ItemTemplate>
<a runat="server" ID="link"> Link to erroneous Milestone </a>
<%# ((MttImportValidationMessage)Container.DataItem).Message %>
<br />
</ItemTemplate>
</asp:Repeater>