How Recognize The CammandName Of A LinkButton Inside An ItemTemplate Of A RadListBox

[Majid Darab]

hi my dear friends :
i added an itemtemplate to my radlistbox and also added 1 label and 2 linkbutton in it ...
my radlistbox is like below :

<telerik:RadListBox ID="RadlbOfImageGroup" runat="server" DataKeyField="ID" DataSortField="Title"
    DataSourceID="sdsImagesGroup" DataTextField="Title" DataValueField="ID" Skin="BlackByMe"
    EnableEmbeddedSkins="False" Width="260px" Height="365px" EmptyMessage="no rec!"
    AutoPostBack="True" OnSelectedIndexChanged="RadlbOfImageGroup_SelectedIndexChanged"
    CausesValidation="False">
    <ItemTemplate>
        <table style="width: 100%;">
            <tr style="width: 100%;">
                <td style="width: 64%;">
                    <asp:Label ID="lblTitleOfIG" runat="server" CssClass="lbl_ListBox_IG_Title" Text='<%# Eval("Title") %>'></asp:Label>
                </td>
                <td style="width: 18%; text-align: center;">
                    <asp:LinkButton ID="lbEditIG" runat="server" CausesValidation="False" CommandName="Edit"
                        CssClass="lb_ListBox_IG" OnClick="lbEditIG_Click">Edit</asp:LinkButton>
                </td>
                <td style="width: 18%; text-align: center;">
                    <asp:LinkButton ID="lbDeleteIG" runat="server" CausesValidation="False" CommandName="Delete"
                        CssClass="lb_ListBox_IG" OnClick="lbDeleteIG_Click">Delete</asp:LinkButton>
                </td>
            </tr>
        </table>
    </ItemTemplate>
</telerik:RadListBox>

My Problem Is how can i check the CommandName of LinkButtons in code behind when i click on them?
(we do n't have access to these LinkButtons In CodeBehind)

thanks for your attention
best regards

[Shinu]

Hello Majid,

One approach is to access the LinkButton using the default argument Sender. Here is a sample code.
C#:

protected void lbDeleteIG_Click(object sender, EventArgs e)
   {
       LinkButton btn = sender as LinkButton;
       if (btn.CommandName=="Delete")
       {
           Response.Write("Deleted");
       }
   }

Thanks,
Shinu.

[Robert]

I'm having a related problem.

I have a RadListBox inside an RadAjaxPanel. When I add an ImageButton to the ItemTemplate for the RadListBox and and then click that button, my page throws the following exception:

Sys.WebForms.PageRequestManagerServerErrorException: Input string was not in a correct format.

Debugging this I've found that it's not my code throwing the exception. Even having a completely empty event handler results in the same problem. Here is the stack trace that I see:

>   Galen.MCF.Web.UI.DLL!MyCompany.MyPage.OnError(System.EventArgs e) Line 450  C#
    System.Web.dll!System.Web.UI.Page.HandleError(System.Exception e) + 0x55 bytes
    System.Web.dll!System.Web.UI.Page.ProcessRequestMain(bool includeStagesBeforeAsyncPoint, bool includeStagesAfterAsyncPoint) + 0x1a79 bytes
    System.Web.dll!System.Web.UI.Page.ProcessRequest(bool includeStagesBeforeAsyncPoint, bool includeStagesAfterAsyncPoint) + 0x84 bytes
    System.Web.dll!System.Web.UI.Page.ProcessRequest() + 0x51 bytes
    System.Web.dll!System.Web.UI.Page.ProcessRequestWithNoAssert(System.Web.HttpContext context) + 0x16 bytes
    System.Web.dll!System.Web.UI.Page.ProcessRequest(System.Web.HttpContext context) + 0x32 bytes
    App_Web_fncgkc2z.dll!ASP.mypage_aspx.ProcessRequest(System.Web.HttpContext context) + 0x33 bytes    C#

The exception's stack trace is:

at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
at System.Number.ParseInt32(String s, NumberStyles style, NumberFormatInfo info)
at System.Web.UI.WebControls.ImageButton.LoadPostData(String postDataKey, NameValueCollection postCollection)
at System.Web.UI.WebControls.ImageButton.System.Web.UI.IPostBackDataHandler.LoadPostData(String postDataKey, NameValueCollection postCollection)
at System.Web.UI.Page.ProcessPostData(NameValueCollection postData, Boolean fBeforeLoad)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

The markup looks like:

<telerik:RadAjaxPanel ID="rapItemSelector" runat="server" EnableAJAX="true">
    <telerik:RadListBox ID="lstFavoriteItems" runat="server" Width="100%"
            AutoPostBack="True" OnSelectedIndexChanged="SelectedItemChanged"
            DataKeyField="Id" DataValueField="DisplayName" RegisterWithScriptManager="true">
        <ItemTemplate>
            <%# DataBinder.Eval(Container, "DataItem.DisplayName") %>
            <asp:ImageButton ID="btnAddFavorite" runat="server"
                    ImageUrl="~/Images/fav_gray.gif"
                    CausesValidation="False"
                    CommandName="Test"
                    CommandArgument="Test"
                    OnClick="AddFavoriteClicked" />
        </ItemTemplate>
    </telerik:RadListBox>
</telerik:RadAjaxPanel>

[Nencho]

Hello Robert,

I have inspected the provided snippet of code and tested it at my side, but I was unable to replicate the faced issue. Here's a video, demonstrating the behavior at my end. I would like to ask you to submit a support ticket along with a runnable sample attached demonstrating the faced exception, in order to investigate the issue further.

All the best,
Nencho
the Telerik team