Saving a comment from inside an updatepanel in a repeater

Question

(Asp.net 4) I have a blog where i use a repeater to show all the blog-articles and the comments to each blog. I'm trying to change how the users can post comments to the blog. I want to put the comments under each blog in an UpdatePanel, and when they write a comment and click on a save-button, i want to refresh the comments, so their new comment will show. But I'm having difficulties achieving this. I've added the UpdatePanel in the ItemTemplate of the Repeater, and added the Textboxes and Button for saving the comment. Each UpdatePanel is placed in a with the id of the blog. But I don't know how to create the code for saving the comment for the correct blog-id, and then to refresh that UpdatePanel.

Code:

<asp:Repeater ID="RepeaterBlog" runat="server">
            <ItemTemplate>        
                <article>  
                    <% if (repeaterCounter == 0)
                       {
                           Response.Write("<header class=\"firstArticleInBlog\">");
                       }
                       else
                       {
                           Response.Write("<header class=\"normalArticle\">");
                       }
                    %>  
                    <h2><%# Eval("article_header") %>  &nbsp;<span class="date">
                    <time datetime="<%# GetPubDate(Eval("article_date")) %>"><%# FormatDate(Eval("article_date")) %></time></span></h2></header>

                    <p><%# Eval("article_content") %><p><br />
                    <div class="comments">                
                    <div class="showhidecomments">
                        <!--<a class="iframe-comments" data-fancybox-type="iframe" href='WriteComments.aspx?BlogId=<%# DataBinder.Eval(Container, "DataItem.id") %>'>Skriv kommentar</a> | -->
                        <a href="javascript:void(0);" title="i<%# Eval("id") %>">Vis/Skriv kommentarer (<%# CountComments (DataBinder.Eval(Container, "DataItem.id")) %>)</a> | <a href="javascript:void(0);" title="i<%# Eval("id") %>" >Skjul kommentarer</a>
                    </div>
                    <section>
                    <article>
                    <div id="i<%# Eval("id") %>" style="display: none;">
                        <asp:UpdatePanel ID="upPanel" runat="server">
                            <Triggers>
                                <asp:AsyncPostBackTrigger ControlID="cmdSaveComment" EventName="Click" />
                            </Triggers>
                            <ContentTemplate>
                                <%# GetComments (DataBinder.Eval(Container, "DataItem.id")) %>
                                <asp:TextBox ID="txtName" runat="server" />
                                <asp:TextBox ID="txtComment" runat="server" TextMode="MultiLine" />
                                <asp:Button ID="cmdSaveComment" runat="server" OnClick="cmdSaveComment_Click" />
                            </ContentTemplate>    
                        </asp:UpdatePanel>
                        </div>                   
                    </article>
                    </section>
                    </div>
                    <% repeaterCounter++; %>
                </article>
            </ItemTemplate>            
            </asp:Repeater>

And in the code-behind:

protected void cmdSaveComment_Click(object sender, EventArgs e)
        {
            //simplified code:
            string name = txtName.Text;
            string comment = txtComment.Text;
            int blogId = (int)(Eval("DataItem.id"));

            dataHandler.NewComment(name, comment, blogId);            
        }

Am i at least close to something here, or am i completely on the wrong track?

Jack Pettinger Jack Pettinger · Accepted Answer · 2013-04-21T09:28:36

You need to use the ItemCommand property for the repeater and the CommandName property for your button.

First declare the event name for the repeater and the button's command name in your aspx. Note the CommandName replaces the OnClick for your button. Also you give the button a command argument, this being the ID for the article record that the comment is for.

<asp:Repeater ID="RepeaterBlog" runat="server" OnItemCommand="RepeaterBlog_ItemCommand">

<asp:Button ID="cmdSaveComment" runat="server" CommandName="SaveComment" CommandArgument='<%# Eval("id")%>' />

Now add this in the code behind

void RepeaterBlog_ItemCommand(Object Sender, RepeaterCommandEventArgs e) {        
  if(e.CommandName == "SaveComment") {
    string name = ((TextBox)e.Item.FindControl("txtName")).Text;
    string comment = ((TextBox)e.Item.FindControl("txtComment")).Text;
    dataHandler.NewComment(name, comment, e.CommandArgument);
  }
}

That should get you started

Saving a comment from inside an updatepanel in a repeater

1 Answers