占位符不显示超链接

时间:2012-10-22 08:52:24

标签: asp.net repeater

我的要求与stockoverflow标签显示相同。我有一个转发器控件,我绑定几列。现在我想显示与相应线程关联的不同标签。请找代码......

<asp:Repeater ID="repForumThread" runat="server">
            <HeaderTemplate>
            </HeaderTemplate>
            <ItemTemplate>
                <table width="100%">
                    <tr>
                        <td>                            
                            <asp:HyperLink ID="hlCategory" runat="server"     NavigateUrl='<%#GetRouteUrl("CategoryRoute", new {CategoryNo= Eval("CategoryId"),CategoryName = Eval("CategoryTitle").ToString().ToLower().Trim().Replace(" ","-")}) %>'
                            Text='<%# DataBinder.Eval(Container.DataItem, "CategoryTitle")%>'></asp:HyperLink>
                    </td>
                </tr>
                <tr>
                    <td>
                        <asp:Label ID="lblThreadTitle" runat="server" Text='<%# DataBinder.Eval(Container.DataItem, "ThreadTitle") %>'></asp:Label>
                    </td>
                </tr>
                <tr>
                    <td>                            
                        <asp:HyperLink ID="hlThreadCreatedBy" runat="server" NavigateUrl='<%#GetRouteUrl("ProfileRoute", new {Member= Eval("MemberId"),MemberName = Eval("ThreadCreatedBy").ToString().ToLower().Trim().Replace(" ","-")}) %>'
                            Text='<%# DataBinder.Eval(Container.DataItem, "ThreadCreatedBy")%>'></asp:HyperLink>
                    </td>
                </tr>
                <tr>
                    <td>
                        <asp:Label ID="lblCreatedOn" runat="server" Text='<%#DataBinder.Eval(Container.DataItem,"ThreadCreatedOn") %>'></asp:Label>
                    </td>
                </tr>
                <tr>
                    <td>
                        <asp:Label ID="lblDescription" runat="server" CssClass="HeaderTextSmall" Text='<%#DataBinder.Eval(Container.DataItem, "ThreadDescription")%>'></asp:Label>
                    </td>
                </tr>
                <tr>
                    <td>
                        <asp:PlaceHolder ID="phTag" runat="server"></asp:PlaceHolder>
                    </td>
                </tr>
            </table>
        </ItemTemplate>
        <FooterTemplate>
        </FooterTemplate>
    </asp:Repeater>


    public void BindRepForumThread()
            {
                SqlConnection dBConnection = null;
                try
                {
                    dBConnection = new SqlConnection();
                    DataTable dtTag = new DataTable();
                    dBConnection.ConnectionString = ConfigurationManager.ConnectionStrings["Conn"].ConnectionString;
                    SqlDataAdapter dataAdapter = new SqlDataAdapter();

                    SqlCommand cmd = new SqlCommand("SP_GetThreadDetails", dBConnection);
                    cmd.CommandType = CommandType.StoredProcedure;
                    cmd.Parameters.Add("@threadId", SqlDbType.Int).Value = threadId;

                    dBConnection.Open();
                    dataAdapter.SelectCommand = cmd;
                    DataSet ds = new DataSet();
                    dataAdapter.Fill(ds);

                    if (ds.Tables[0].Rows.Count > 0)
                    {
                        DataTable dtThread = new DataTable();
                        DataRow drThread;
                        dtThread.Columns.Add("ThreadId");
                        dtThread.Columns.Add("CategoryId");
                        dtThread.Columns.Add("CategoryTitle");
                        dtThread.Columns.Add("ThreadTitle");
                        dtThread.Columns.Add("ThreadDescription");
                        dtThread.Columns.Add("ThreadCreatedBy");
                        dtThread.Columns.Add("ThreadCreatedOn");
                        dtThread.Columns.Add("MemberId");
                        dtThread.Columns.Add("TagId");
                        dtThread.Columns.Add("TagDescription");

                        foreach (DataRow dr in ds.Tables[0].Rows)
                        {
                            drThread = dtThread.NewRow();

                            drThread["ThreadId"] = dr["T_ThreadId"];
                            drThread["CategoryId"] = dr["C_CategoryId"];
                            drThread["CategoryTitle"] = dr["C_CategoryTitle"];
                            drThread["ThreadTitle"] = dr["T_ThreadTitle"];
                            drThread["ThreadDescription"] = dr["T_ThreadDescription"];
                            drThread["ThreadCreatedBy"] = dr["Mem_MemberUserName"];
                            drThread["ThreadCreatedOn"] = dr["T_ThreadCreatedOn"];
                            drThread["MemberId"] = dr["T_ThreadCreatedBy"];

                            if (ds.Tables[1].Rows.Count > 0)
                            {
                                phTag.Controls.Clear();

                                foreach (DataRow dr1 in ds.Tables[1].Rows)
                                {
                                    HyperLink hlTag = new HyperLink();
                                    hlTag.Text = dr1["Tg_TagName"].ToString();
                                    int TagId = Convert.ToInt32(dr1["Tg_TagId"].ToString());
                                    hlTag.ID = "hlTag" + TagId.ToString();

                                    hlTag.NavigateUrl = hlTag.GetRouteUrl("TagRoute", new { Id = TagId, TagName = hlTag.Text.ToString().ToLower().Trim().Replace(" ", "-") });
                                    phTag.Controls.Add(hlTag);
                                }
                            }

                            dtThread.Rows.Add(drThread);
                        }

                        repForumThread.DataSource = dtThread;
                        repForumThread.DataBind();

                        dBConnection.Close();
                    }
                }
                catch (Exception Ex)
                {
                    throw Ex;
                }
                finally
                {
                    // Close data reader object and database connection
                    if (dBConnection.State == ConnectionState.Open)
                        dBConnection.Close();
                }
            }

evreything工作正常。我能够动态生成超链接,但我无法显示创建的超链接&amp;它为占位符抛出错误“对象引用未设置为对象的实例”。

提前致谢。

1 个答案:

答案 0 :(得分:1)

我已经解决了这个问题。我缺少OnItemCreated转发器控制功能,我们可以找到一个占位符控制器和然后我们可以动态添加超链接。

protected void repForumThread_ItemCrteated(object sender, RepeaterItemEventArgs e)
        {
            DataRowView drv = e.Item.DataItem as DataRowView;
            DataTable dtTag = new DataTable();
            if (Cache["TagData"] != null)
            {
                dtTag = (DataTable)Cache["TagData"];
            }
            if (dtTag.Rows.Count > 0)
            {
                if (e.Item.ItemType == ListItemType.AlternatingItem || e.Item.ItemType == ListItemType.Item)
                {

                    PlaceHolder plTag = e.Item.FindControl("phTag") as PlaceHolder;
                    if (plTag != null)
                    {
                        plTag.Controls.Clear();
                        foreach (DataRow dr1 in dtTag.Rows)
                        {

                            HyperLink hlTag = new HyperLink();
                            hlTag.Text = dr1["Tg_TagName"].ToString();
                            int TagId = Convert.ToInt32(dr1["Tg_TagId"].ToString());
                            hlTag.ID = "hlTag" + TagId.ToString();

                            hlTag.NavigateUrl = hlTag.GetRouteUrl("TagRoute", new { Id = TagId, TagName = hlTag.Text.ToString().ToLower().Trim().Replace(" ", "-") });
                            plTag.Controls.Add(hlTag);
                        }
                    }
                }
            }
        }