c# - 如何访问用户控件页面 ListView 中动态创建的表的文本框？

Question

实际上我正在使用 asp.net 和 c# 开发 Web 模板。我有包含用户控制页面的 maintemp.aspx 页面。在我的用户控件中，我有一个 ListView ，在这个 ListView 中，我必须基于 XML 文件在 ItemTemplate 中创建动态表。

我的 ListView 代码包括 ItemTemplate 是:

<asp:ListView ID="lv_Uc_Module" runat="server"
                    onitemediting="lv_Uc_Module_ItemEditing" 

                    onitemcanceling="lv_Uc_Module_ItemCanceling" 
                    onitemdeleting="lv_Uc_Module_ItemDeleting"  
                    OnItemDataBound="lv_Uc_Module_ItemDataBound"
                    OnSorting="lv_Uc_Module_Sorting">

                        <LayoutTemplate>
                            <asp:Table runat="server" ID="table_Lv_Layout">
                                <asp:TableRow runat="server" ID="tr_Table_Layout">
                                    <asp:TableCell runat="server" ID="td_Table_Layout">
                                        <asp:Table runat="server" ID="itemPlaceholderContainer">
                                            <asp:TableRow runat="server" ID="tr_Table_IphContainer">

                                                <asp:TableHeaderCell runat="server">
                                                    <asp:PlaceHolder ID="th_Ph_Lv_header" runat="server"></asp:PlaceHolder>
                                                </asp:TableHeaderCell>
                                            </asp:TableRow>
                                            <asp:TableRow runat="server">
                                                <asp:TableCell runat="server">

                                                    <asp:PlaceHolder runat="server" ID="itemPlaceholder" />

                                                </asp:TableCell>

                                            </asp:TableRow>
                                        </asp:Table>
                                    </asp:TableCell>
                                </asp:TableRow>
                                <asp:TableRow runat="server" ID="tr_Validate_Table_Layout">
                                    <asp:TableCell runat="server" ID="td_Validate_Table_Layout" HorizontalAlign="Center" BackColor="#CCCCCC">
                                        <asp:ValidationSummary ID="ValidationSummary1" runat="server" HeaderText="You received the following errors:" ShowMessageBox="true" ShowSummary="false" ValidationGroup="VGEditTmp" />

                                    </asp:TableCell>
                                </asp:TableRow>
                            </asp:Table>
                            <br />
                            <asp:DataPager ID="lv_DataPager" runat="server" PagedControlID="lv_Uc_Module" PageSize="25" OnPreRender="lv_DataPager_PreRender">
                                <Fields>
                                    <asp:NextPreviousPagerField ButtonType="Image" ShowFirstPageButton="true" ShowLastPageButton="true" FirstPageImageUrl="~/Images/First.png" LastPageImageUrl="~/Images/Last.png" NextPageImageUrl="~/Images/Next.png" PreviousPageImageUrl="~/Images/Previous.png" />
                                    <asp:TemplatePagerField>
                                        <PagerTemplate>
                                            <span style="color:Blue;">

                                            </span>
                                        </PagerTemplate>
                                    </asp:TemplatePagerField>
                                </Fields>
                            </asp:DataPager>
                        </LayoutTemplate>

                        <ItemTemplate>
                            <asp:TableRow runat="server">
                                <asp:TableCell runat="server">

                                    <asp:Table runat="server" ID="Table_Lv_ItemTemplate"></asp:Table>
                                </asp:TableCell>
                                <asp:TableCell runat="server">
                                    <asp:Button ID="btn_Edit" runat="server" CommandName="Edit" Text="" CssClass="btn_Edit" CausesValidation="True" Visible="false" />
                                    <asp:Button ID="btn_Delete" runat="server" CommandName="Delete" Text="" CssClass="btn_Delete" CausesValidation="false" OnClientClick="return confirm('Are you sure you want to delete this item?');" Visible="false" />
                                </asp:TableCell>
                            </asp:TableRow>

                        </ItemTemplate>

正如您在 listview ItemTemplate 部分看到的那样，我放了一个 with ID = "Table_Lv_ItemTemplate"，我在这里创建了动态表。

我已将动态表代码放在 ItemDataBound 函数中，如下所示:

protected void lv_Uc_Module_ItemDataBound(object sender, ListViewItemEventArgs e)
{
    if (tempDataBound == 0 && !"".Equals(hid_ChooseModule.Value))
    {
        XmlDocument xDocRead = new XmlDocument();
        xDocRead.Load(Server.MapPath("ModuleTemp.xml"));
        lv_Uc_Module_DataBind("");

        Table table_Lv_ItemTemplate = (Table)e.Item.FindControl("Table_Lv_ItemTemplate");
        table_Lv_ItemTemplate.Controls.Clear();
        //table_Lv_ItemTemplate.Dispose();

        tempDataBound++;
    }

    if (e.Item.ItemType == ListViewItemType.DataItem)
    {
        XmlDocument xDocRead = new XmlDocument();
        xDocRead.Load(Server.MapPath("ModuleTemp.xml"));
        string xModuleName = hid_ChooseModule.Value;
        XmlNode xColCounter;
        TableRow tr_DataBound = new TableRow();
        TableRow tr_Lv_Header = new TableRow();

        if (!"".Equals(hid_ChooseModule.Value))
        {
            xColCounter = xDocRead.SelectSingleNode("ModuleTemp/" + xModuleName + "/List");
        }
        else
        {
            xModuleName = xDocRead.SelectSingleNode("ModuleTemp").FirstChild.Name;
            xColCounter = xDocRead.SelectSingleNode("ModuleTemp/" + xModuleName + "/List");
        }
        int pkCounter = 0, nonPkCounter = 0, colCount = xColCounter.ChildNodes.Count;
        string[] primaryKey = new string[30];
        string[] nonPrimaryKey = new string[colCount + 1];

        for (int i = 1; i <= colCount; i++)
        {
            if (xDocRead.SelectSingleNode("ModuleTemp/" + xModuleName + "/Edit/TableColumn" + i).Attributes.GetNamedItem("IsPrimaryKey").Value == "Y")
            {
                primaryKey[pkCounter] = xDocRead.SelectSingleNode("ModuleTemp/" + xModuleName + "/Edit/TableColumn" + i).Attributes.GetNamedItem("Name").Value;
                pkCounter++;
            }
            else
            {
                nonPrimaryKey[nonPkCounter] = xDocRead.SelectSingleNode("ModuleTemp/" + xModuleName + "/Edit/TableColumn" + i).Attributes.GetNamedItem("Name").Value;
                nonPkCounter++;
            }
        }

        System.Data.DataRowView rowView = e.Item.DataItem as System.Data.DataRowView;
        TableCell tc_Lv_Header = new TableCell();
        if (!"".Equals(hid_ChooseModule.Value))
        {
            if (tempHeader == 0)
            {
                tempHeader++;
                for (int i = 1; i <= pkCounter + nonPkCounter; i++)
                {
                    tc_Lv_Header = new TableCell();
                    Label lb = new Label();

                    if (i <= pkCounter)
                    {
                        lb.Text = primaryKey[i - 1];
                    }
                    else
                    {
                        lb.Text = nonPrimaryKey[i - pkCounter - 1];
                    }

                    lb.ID = "lb" + i + "_Table_IphContainer";
                    tc_Lv_Header.Controls.Add(lb);
                    tc_Lv_Header.CssClass = "th_ItemTemplate";
                    tr_Lv_Header.Cells.Add(tc_Lv_Header);
                }

                tr_Lv_Header.Cells.Add(tc_Lv_Header);

                table_Header.Rows.Add(tr_Lv_Header);
                PlaceHolder th_Ph_Lv_Hedear = (PlaceHolder)lv_Uc_Module.FindControl("th_Ph_Lv_header");
                th_Ph_Lv_Hedear.Controls.Add(table_Header);
            }
        }
        TableCell tc_DataBound = new TableCell();

        if (editTempSelection == e.Item.DataItemIndex)
        {
            for (int i = 1; i <= pkCounter + nonPkCounter; i++)
            {
                tc_DataBound = new TableCell();
                TextBox tb = new TextBox();
                tb.Width = 110;
                tb.Text = rowView[i - 1].ToString();
                tb.ID = "td_EditTemp" + i + "_" + e.Item.DataItemIndex;
                tc_DataBound.Controls.Add(tb);
                tc_DataBound.CssClass = "td_Tb_ItemTemplate";
                tr_DataBound.Cells.Add(tc_DataBound);
            }
        }
        else
        {
            for (int i = 1; i <= pkCounter + nonPkCounter; i++)
            {
                tc_DataBound = new TableCell();
                Label lb = new Label();
                lb.Text = rowView[i - 1].ToString();
                lb.ID = "lb_ItemTemp" + i + "_" + e.Item.DataItemIndex;
                tc_DataBound.Controls.Add(lb);
                tc_DataBound.CssClass = "td_Lb_ItemTemplate";
                tr_DataBound.Cells.Add(tc_DataBound);
            }
        }
        // add button to the columns
        if (editTempSelection != e.Item.DataItemIndex)
        {
            tc_DataBound = new TableCell();
            Button btn_Edit = new Button();
            btn_Edit.ID = "btn_Edit";
            btn_Edit.CommandName = "Edit";
            btn_Edit.CssClass = "btn_Edit";
            btn_Edit.CausesValidation = true;
            tc_DataBound.Controls.Add(btn_Edit);
            tr_DataBound.Cells.Add(tc_DataBound);

            tc_DataBound = new TableCell();
            Button btn_Delete = new Button();
            btn_Delete.ID = "btn_Delete";
            btn_Delete.CommandName = "Delete";
            btn_Delete.CssClass = "btn_Delete";
            btn_Delete.CausesValidation = false;
            btn_Delete.OnClientClick = "return confirm('Are you sure you want to delete this item?');";
            tc_DataBound.Controls.Add(btn_Delete);
            tr_DataBound.Cells.Add(tc_DataBound);
        }
        else
        {
            tc_DataBound = new TableCell();
            Button btn_Update = new Button();
            btn_Update.ID = "btn_Update";
            btn_Update.CommandName = "Update";
            btn_Update.CssClass = "btn_Update";
            btn_Update.ValidationGroup = "VGEditTmp";
            tc_DataBound.Controls.Add(btn_Update);
            tr_DataBound.Cells.Add(tc_DataBound);

            tc_DataBound = new TableCell();
            Button btn_Cancel = new Button();
            btn_Cancel.ID = "btn_Cancel";
            btn_Cancel.CommandName = "Cancel";
            btn_Cancel.CssClass = "btn_Cancel";
            btn_Cancel.CausesValidation = false;
            tc_DataBound.Controls.Add(btn_Cancel);
            tr_DataBound.Cells.Add(tc_DataBound);
            tr_DataBound.CssClass = "tr_Edit_ItemTemplate";
        }

        if (editTempSelection == e.Item.DataItemIndex)
        {
            lv_Uc_Module_ItemUpdating(sender, e.Item.DataItemIndex);
        }
        // add columns to the row
        tr_DataBound.Cells.Add(tc_DataBound);
        Table table_Lv_ItemTemplate = (Table)e.Item.FindControl("Table_Lv_ItemTemplate");
        table_Lv_ItemTemplate.Rows.Add(tr_DataBound);
    }
}

此数据绑定(bind)的结果如下图所示。它动态地从 XML 文件中读取数据并创建表。

一旦用户点击下图的编辑按钮，他们就可以编辑行数据。

问题在这里，我无法访问这些文本框来获取它们的数据并更新数据库。而且我无法删除行。

我试过 TextBox tempLabelLv = (TextBox)add_Table.FindControl("td_EditTemp2_5"); add_Table 是我的动态表 ID，我试过 TextBox tempLabelLv = (TextBox)lv_Uc_Module.FindControl("td_EditTemp2_5"); lv_Uc_Module 是我的 ListView ID。但我仍然无法访问这些文本框。

能否请您指导我如何克服这个问题，并获取这些文本框的数据来更新数据库？感谢您的考虑。

Answer 1

这只是一个猜测，所以如果不正确，请不要打分:D 好吧，假设您有一个动态创建的页面。动态创建中的元素自然不会成为设计文件的一部分，对吗？所以说我通过一些脚本动态创建一个标签，现在我想进入它。我认为，我还可以通过手动引入它来增加识别度。所以要访问该标签，我会这样做:

public class yourPageOrClassNameOrSomethingOrAnotherOrIDontKnow: System.Web.UI.Page
{
    protected System.Web.UI.WebControls.Label myLabel;
...
}

现在即使我动态创建它也可以访问它。但是，如果您有动态创建的中继器或 ListView 或您拥有的东西，请务必注册它，然后使用您之前描述的方法( TextBox tempLabelLv = (TextBox)add_Table.FindControl("td_EditTemp2_5"); )找到它. (在上面的示例中，您将使用 protected System.Web.UI.HtmlControls.HtmlTable add_Table; 注册“add_Table”“希望这能有所帮助。如果没有，我试过了。=)