We Keep Coding

How to find which control triggers the event inside a repeater

How to find which control event got triggered, for example, if there are 5 columns in the repeater if the 2nd checkbox or 3rd drop-down list causes the event. How to find which control event got triggered, so that the particular control related logic alone will be executed without disturbing other column controls.
The sample repeater code is attached as follows,
<asp:Repeater ID="rptTest" runat="server">
<ItemTemplate>
<td class="repeater-col">
<div>
<asp:TextBox ID="txt1" runat="server"></asp:TextBox>
</div>
<div>
<asp:DropDownList ID="ddl1" runat="server" OnSelectedIndexChanged="ddl1_SelectedIndexChanged" AutoPostBack="true">
</asp:DropDownList>
</div>
<div>
<asp:CheckBox ID="chk1" runat="server" OnCheckedChanged="chk1_CheckedChanged" AutoPostBack="true" />
</div>
</td>
</ItemTemplate>
</asp:Repeater>
There are lot more dependent controls presented inside the repeater. Based on the selection of the controls the data to the other controls are bound and processed. The logic bounded to the repeater will be handled on the respective events for example on chk1_CheckedChanged and ddl1_SelectedIndexChanged
Kindly help on this! Thanks in advance!

You can cast the sender back to the correct Control type. Then you can access it's properties. If you want to know which items the control was in, you can use the NamingContainer
protected void ddl1_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList drp = sender as DropDownList;
drp.BackColor = Color.Green;
RepeaterItem item = drp.NamingContainer as RepeaterItem;
int itemIndex = item.ItemIndex;
}

How to avoid post-back of Check Box inside repeater

I am newbie for asp.net,
I have a repeater which contains check box,whenever I check the check box I am firing an event on checkchanged,but the page postbacks.
I have an update panel for the entire content in my page,but still postback occurs.Is there anyway to avoid postback.
(Ps:To avoid Postback,I am meaning to avoid the flicker that occurs)
Thanks
<asp:Repeater ID="rptrDepartment" runat="server" OnItemCommand="rptrDepartment_ItemCommand"
OnItemDataBound="rptrdepartment_databound">
<ItemTemplate>
<tr>
<td>
<asp:CheckBox ID ="chkRow" runat="server" OnCheckedChanged="ChkRow_ChkChanged" AutoPostback="true" />
</td>
</tr>
</ItemTemplate>
</asp:Repeater>
And in my .cs page,
protected void ChkRow_ChkChanged(object sender, EventArgs e)
{
//some method
}

Just keep your repeater inside update panel rather than entire page, if you want some other controls also need partial postback then you can go for multiple update panels.

ASP.NET ListView control not firing OnItemCommand Event

I know that this sounds like a number of other posts, all of which I have read but have not addressed my issue.
Here's the Scenario ...
I have BOTH a Repeater and a ListView bound to the same Data Source. Each control contains an ASP:LinkButton which, when clicked, should fire the OnItemCommand event. Although they are wired to the EXACT same data at the EXACT same places in the page life cycle and View State is enabled for the page and each individual control the Repeater appears to fire the event and the ListView does not.
I know that the event will not fire if the data is not bound BEFORE the assignment of the event handler. I am relying on ViewState to repopulate the controls when the page is posted back to. Looking at each control in debug mode while stepping through a request I can see that the Repeater DOES indeed appear to repopulated with the ViewState data but the ListView does not.
As these are both generated, populated, bound, and handled almost IDENTICALLY I am at a complete loss why this may be happening. I have also noticed a similar issue with the GridView control (it does NOT fire the event). I assume that these are related somehow.
The only thing that I can think of that the GridView and ListView have in common that the Repeater does not is the built-in paging capability. Whether implemented or not is there something with the paging that affects the loading of the ViewState?
OrderControl.ASCX is a control which exposes the ListView and Repeater as properties (OrderListLV & OrderListRPT) to the host page/application.
<asp:ListView runat="server" id="lvOrderList" OnItemDataBound="lstOrderList_OnItemDataBound" EnableViewState="true" >
<LayoutTemplate>
<table class="tblGrid">
<tr runat="server" id="itemPlaceholder" />
</table>
<ASP:DataPager runat="server" ID="dataPager1" PageSize="3">
<Fields>
<ASP:NextPreviousPagerField
ButtonType="Button"
ShowFirstPageButton="true"
ShowLastPageButton="true"
ShowNextPageButton="true"
ShowPreviousPageButton="true" />
</Fields>
</ASP:DataPager>
</LayoutTemplate>
<ItemTemplate>
<tr class="row-">
<td align="center"><ASP:LinkButton runat="server" id="lnkOrderId1" /></td>
</tr>
</ItemTemplate>
</asp:ListView>
<asp:Repeater runat="server" id="rptOrderList" OnItemDataBound="rptOrderList_ItemDataBound">
<HeaderTemplate>
<table class="tblGrid">
</HeaderTemplate>
<ItemTemplate>
<tr">
<td align="center"><ASP:LinkButton runat="server" id="lnkOrderId" /></td>
</tr>
</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>
OrderControl.ASCX.CS is where the controls are bound to the data source in the Pre-Render stage, well after ViewState has had the opportunity to reconstitute itself.
protected override void OnPreRender(EventArgs e)
{
this.lstOrderList.DataSource = this.OrderHeaders.OrderByDescending(x => x.OrderDate).ToList();
this.lstOrderList.DataBind();
this.rptOrderList.DataSource = this.OrderHeaders.OrderByDescending(x => x.OrderDate).ToList();
this.rptOrderList.DataBind();
}
Host.ASPX.CS is the page which consumes the control. It attaches the event handlers directly the controls in it's OnLoad handler.
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
this.OrderControl.OrderListRPT.ItemCommand += new RepeaterCommandEventHandler(OrderList2_ItemCommand);
this.OrderControl.OrderListLV.ItemCommand += new EventHandler<ListViewCommandEventArgs>(OrderList_ItemCommand);
}
After all is said and done when I click on the LinkButton in each control the ItemCommand Handler for the Repeater fires and executes correctly but the process doesn't even enter the handler for the ListView handler.
I am crazy confused on this issue. I am hoping that someone might have some thoughts on this. Something I can try at least?
Thanks,
Gary

you should set the CommandName property of each LinkButton in the ListView, eventually also the CommandArgument.
<td align="center">
<asp:LinkButton runat="server" id="lnkOrderId1" CommandName="yourCommandName" CommandArgument="yourCommandArgument" />
</td>
also check asked questions here in SO before posting a new question ;-)
listview OnItemCommand dosen't fire up

Need help with repeater

This is my repeater:
<asp:Repeater ID="myRepeater" OnItemCommand="myRepeater_ItemCommand" runat="server" OnItemDataBound="myRepeater_OnItemDataBound">
<HeaderTemplate>
<table width="99%" border="0" cellpadding="0" cellspacing="0">
<tr class="lgrey">
<td>Default</td>
</tr>
</HeaderTemplate>
<ItemTemplate>
<table>
<tr>
<td>
<asp:LinkButton ID="lnk1" Text="Make Default" CommandName="SetDefault" runat="server" Visible="True" CommandArgument='<%#Eval("UserID") %>' CausesValidation="false"></asp:LinkButton>
<asp:Label ID="label1" Text="Yes" runat="server" Visible="False"></asp:Label>
</td>
</tr>
</ItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>
What I want is that when user clicks on any of
the "lnk1" link button in the list that repeater renders,
the link should be replaced with the label "label1"..
i.e. when the user clicks on "Make Default" link, it should be replaced with "Yes" label
Calling this method obj.SetDefaultAddress(); is setting the default address in the DB alright..
problem is with the display of the label1 and lnk1 when the repeater renders...
what is happening is that BOTH "Make Default" LinkButton and the "YES" label are getting displayed
under the "Default" column of the table inside my repeater.
I want some code that will check the "IsDefault" value in my DB and display "Make Default " link button
and "YES" label accordingly... i.e. if IsDefault's value in the DB is TRUE then "YES" should be displayed in the repeater
otherwise "Make Default"

Are you sure your piece of code in code behind under ItemCommand is executing?
I only changed the CommandName from SetDefault to SetDefaultAddress in aspx file to match with the one in code behind, it worked.

Where to start...
I think what's causing your problem is that the SelectedItem and the DefaultAddress are not mapped to each other, so when you click the button you're getting the selected index set and the OnItemDatabound event is showing/hiding what you want, but when the grid is initialized from the database, the SelectedItem is not being set.
I don't know what your datasource is, and there's obviously more code to this than what you've posted, but if you can look at the e.Item.DataItem in the myRepeater_ItemDataBound handler, you can set the current item as selected when the address is the default (e.Item.ItemType... or use your "selectedIndex" counter)

I will probably do it from markup itself - this is assuming that you have "IsDefault" column/property of bit/boolean type in your data-source indicating the address is default. So use following markup:
...
<tr>
<td>
<asp:LinkButton ID="lnk1" Text="Make Default" CommandName="SetDefault" runat="server" Visible='<%# !Eval("IsDefault") %>' CommandArgument='<%#Eval("UserID") %>' CausesValidation="false"></asp:LinkButton>
<asp:Label ID="label1" Text="Yes" runat="server" Visible='<%# !Eval("IsDefault") %>'></asp:Label>
</td>
</tr>
...
You need to control visibility based on property in your data source (either using markup or ItemDataBound event). Also when SetDefault link is clicked, you must either re-bind the repeater new state or toggle visibility explicitly (as your current code is doing).
EDIT:
If data binding expression are not working then you have to do it in ItemDataBound event. I see that you have already tried that but there is one mistake - bllUsers obj=new bllUsers(); will always have IsDefault as false - you need to use data item. For example,
protected void myRepeater_ItemDataBound(Object sender, RepeaterItemEventArgs e)
{
if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
{
bllUsers obj = e.Item.DataItem as bllUsers;
((Label)e.Item.FindControl("ldefault")).Visible = obj.isDefault;
((Button)e.Item.FindControl("btnMakeDefault")).Visible = ! obj.isDefault;
}
}

How can i access a control within a ListView once a button has been clicked?

I need to access a label control in a listview when I've clicked a button (that is on the same row)...
Does anyone know how to do this please? :(
See below for more of an insight...
ASPX Page:
<asp:ListView ID="ListView1" runat="server" DataSourceID="DataSource">
<LayoutTemplate>//Etc </LayoutTemplate>
<ItemTemplate>
<asp:Label ID="lblDone" runat="server" Visible="false">Your vote has been counted</asp:Label>
<asp:Button ID="voteButton" runat="server" Text="Vote" CommandArgument='<%#Eval("id") %>' OnClick="voteOnThis" />
</ItemTemplate>
Code Behind:
protected void voteOnThis(object sender, EventArgs e)
{
Button myButton = (Button)sender;
Voting.vote(int.Parse(myButton.CommandArgument));
// Here i would like to access the 'label' lblDone and make this Visible
}

In this simple case, I should consider using Javascript (JQuery)
<asp:ListView ID="ListView1" runat="server" DataSourceID="DataSource">
<LayoutTemplate>//Etc </LayoutTemplate>
<ItemTemplate>
<asp:Label ID="lblDone" runat="server" style="visibility:hidden">Your vote has been counted</asp:Label>
<asp:Button OnClientClick="showLblDone()" ID="voteButton" runat="server" Text="Vote" CommandArgument='<%#Eval("id") %>' OnClick="voteOnThis" />
</ItemTemplate>
now, define inside a script tag the showLblDone function:
<script>
function showLblDone (){
$(this).siblings('span').show();}
</script>
You can also call this function with a parameter if you want to show/hide on every click, or you can use .toggle() instead of .show().
In this case you must add a div (or a Panel) inside the ItemTemplate.

You need to hook into the listview row bind and add the information you want to have when clicked. Using this, you can add an attribute to the button that you read back on click, for example...
If you posted some actual code, I could probably help some more.