c# - 如何在 ASP:ListView 中一次批量实现所有插入、更新、删除操作

Question

我有一个 Asp:ListView 控件，我在 Web 表单的弹出窗口中显示该控件。目前，只要我单击插入、更新或删除链接按钮，它就会直接在数据库中进行所有更改。

但是只有在提交 Web 表单时，我才需要在数据库中完成所有更改。
所以，我想我需要在会话中保留绑定到 ListView 的数据，并且在所有插入、更新和删除操作中，通过
步骤 1）手动对 OnInserting、OnDeleting、OnUpdating 事件进行所有更改）检索每次来自 Session["ListView1"] 的数据，
步骤 2) 对检索到的数据执行插入/删除/更新操作
步骤 3) 将其绑定到 ListView
步骤 4) 更新后替换 Session["ListView1"] 中的数据。
第 5 步）在 Web 表单提交时，获取更新的数据并在数据库中全部替换？

我做了这些步骤，但它没有按预期工作。在更新时，ListView 显示 2 列的空白值并错误地绑定数据。我已经绑定了正确的列。插入后，TextBox 没有按预期更改为 Labels。下面是我的 ListView 和代码隐藏代码：

列表显示：

    <asp:updatepanel id="UpdatePanel1" runat="server">
    <ContentTemplate>
        <asp:ListView ID="ListView1" runat="server" 
            OnItemCanceling="ListView1_ItemCanceling" OnItemEditing="ListView1_ItemEditing" 
            OnItemDeleting="ListView1_ItemDeleting" OnItemUpdating="ListView1_ItemUpdating" 
            OnItemInserting="ListView1_ItemInserting" DataKeyNames="Id" 
            InsertItemPosition="LastItem">
        <AlternatingItemTemplate>
            <tr style="">
                <td width="200">
                    <asp:LinkButton ClientIDMode="AutoID" ID="DeleteButton" runat="server" 
                        CommandName="Delete" Text="Delete" CausesValidation="false" />                                                            
                    <asp:LinkButton ClientIDMode="AutoID" ID="EditButton" runat="server" 
                        CommandName="Edit" Text="Edit" CausesValidation="false" />                 
                </td>
                <td>
                    <asp:Label ID="IdLabel" runat="server" Text='<%# Eval("Id") %>' />
                </td>
                <td>
                    <asp:Label ID="FirstNameLabel" runat="server" Text='<%# Eval("FirstName") %>' />
                </td>
                <td>
                    <asp:Label ID="LastNameLabel" runat="server" Text='<%# Eval("LastName") %>' />
                </td>
                <td>
                    <asp:Label ID="Column3Label" runat="server" Text='<%# Eval("Column3") %>' />
                </td>
                <td>
                    <asp:Label ID="Column4Label" runat="server" Text='<%# Eval("Column4") %>' />
                </td>
            </tr>
        </AlternatingItemTemplate>
        <EditItemTemplate>
            <tr style="">
                <td>
                    <asp:LinkButton ClientIDMode="AutoID" ID="UpdateButton" runat="server" 
                        CommandName="Update" Text="Update" ValidationGroup="popup1" CausesValidation="true" />
                    <asp:LinkButton ClientIDMode="AutoID" ID="CancelButton" runat="server" 
                        CommandName="Cancel" Text="Cancel" CausesValidation="false" />
                </td>
                <td>
                    <asp:Label ID="IdLabel1" runat="server" Text='<%# Eval("Id") %>' />
                </td>
                <td>
                    <asp:TextBox ID="FirstNameTextBox" Style="width: 100px; background-color: white;" 
                        runat="server" Text='<%# Bind("FirstName") %>' CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="NameReq" runat="server" ControlToValidate="FirstNameTextBox" 
                        ErrorMessage="First name is required." ToolTip="First name is required." 
                        ValidationGroup="popup1">*</asp:RequiredFieldValidator>
                </td>
                <td>
                    <asp:TextBox ID="LastNameTextBox" Style="width: 100px; background-color: white;" 
                        runat="server" Text='<%# Bind("LastName") %>' CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" 
                        ControlToValidate="LastNameTextBox" ErrorMessage="Last name is required." 
                        ToolTip="Last name is required." ValidationGroup="popup1">*</asp:RequiredFieldValidator>
                </td>
                <td>
                    <asp:TextBox ID="Column3TextBox" Style="width: 100px; background-color: white;" 
                        runat="server" Text='<%# Bind("Column3") %>' CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="RequiredFieldValidator6" runat="server" 
                        ControlToValidate="Column3TextBox" ErrorMessage="ID is required." ToolTip="ID is required." 
                        ValidationGroup="popup1">*</asp:RequiredFieldValidator>
                </td>
                <td>
                    <asp:TextBox ID="Column4Text" placeholder="mm/dd/yyyy" Style="width: 100px; 
                        background-color: white;" runat="server" Text='<%# Bind("Column4") %>' 
                        CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="RequiredFieldValidator7" runat="server" 
                        ControlToValidate="Column4Text" ErrorMessage="Date is required." 
                        ToolTip="Date is required." ValidationGroup="popup1">*</asp:RequiredFieldValidator>
                </td>
            </tr>
            <tr>
                <td>
                    <asp:RegularExpressionValidator ID="dateValRegex" runat="server" 
                        ControlToValidate="Column4Text" ErrorMessage="Please Enter a valid date in the format (mm/dd/yyyy)" 
                        ValidationExpression="^(0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])[- /.](19|20)\d\d$" 
                        ValidationGroup="popup"></asp:RegularExpressionValidator>
                </td> 
            </tr>
        </EditItemTemplate>
        <EmptyDataTemplate>
            <table id="Table1" runat="server" style="">
                <tr>
                    <td>No data was returned.</td>
                </tr>
            </table>
        </EmptyDataTemplate>
        <InsertItemTemplate>
            <tr>
                <td width="200">
                    <asp:LinkButton ClientIDMode="AutoID" ID="InsertButton" runat="server" CommandName="Insert" 
                        Text="Insert" ValidationGroup="popup" CausesValidation="true" />
                    <asp:LinkButton ClientIDMode="AutoID" ID="LinkButton1" runat="server" CommandName="Cancel" 
                        Text="Clear" CausesValidation="false" />
                </td>
                <td>
                    <asp:Label ID="Label1" runat="server" Text='<%# Bind("Id") %>' />
                </td>
                <td>
                    <asp:TextBox ID="TextBox1" Style="width: 100px; background-color: white;" runat="server" 
                        Text='<%# Bind("FirstName") %>' CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" 
                        ControlToValidate="FirstNameTextBox" ErrorMessage="First name is required." 
                        ToolTip="First name is required." ValidationGroup="popup">*</asp:RequiredFieldValidator>
                </td>
                <td>
                    <asp:TextBox ID="TextBox2" Style="width: 100px; background-color: white;" runat="server" 
                        Text='<%# Bind("LastName") %>' CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" 
                        ControlToValidate="LastNameTextBox" ErrorMessage="Last name is required." 
                        ToolTip="Last name is required." ValidationGroup="popup">*</asp:RequiredFieldValidator>
                </td>
                <td>
                    <asp:TextBox ID="TextBox3" Style="width: 100px; background-color: white;" runat="server" 
                        Text='<%# Bind("Column3") %>' CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" 
                        ControlToValidate="Column3TextBox" ErrorMessage="ID is required." 
                        ToolTip="ID is required." ValidationGroup="popup">*</asp:RequiredFieldValidator>
                </td>
                <td>
                    <asp:TextBox ID="TextBox4" placeholder="mm/dd/yyyy" Style="width: 100px; 
                        background-color: white;" runat="server" Text='<%# Bind("Column4") %>' CausesValidation="true" />
                    <asp:RequiredFieldValidator ID="RequiredFieldValidator5" runat="server" ControlToValidate="Column4Text" 
                        ErrorMessage="Date is required." ToolTip="Date is required." 
                        ValidationGroup="popup">*</asp:RequiredFieldValidator>
            </tr>
            <tr>
                <td>
                    <asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" 
                        ControlToValidate="Column4Text" ErrorMessage="Please Enter a valid date in the format (mm/dd/yyyy)" 
                        ValidationExpression="^(0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])[- /.](19|20)\d\d$" 
                        ValidationGroup="popup"></asp:RegularExpressionValidator>
                </td> 
            </tr>
        </InsertItemTemplate>
        <ItemTemplate>
            <tr>
                <td width="200">
                    <asp:LinkButton ClientIDMode="AutoID" ID="LinkButton2" runat="server" CommandName="Delete" 
                        Text="Delete" CausesValidation="false" />
                    <asp:LinkButton ClientIDMode="AutoID" ID="LinkButton3" runat="server" CommandName="Edit" 
                        Text="Edit" CausesValidation="false" />
                </td>
                <td>
                    <asp:Label ID="Label2" runat="server" Text='<%# Eval("Id") %>' />
                </td>
                <td>
                    <asp:Label ID="Label3" runat="server" Text='<%# Eval("FirstName") %>' />
                </td>
                <td>
                    <asp:Label ID="Label4" runat="server" Text='<%# Eval("LastName") %>' />
                </td>
                <td>
                    <asp:Label ID="Label5" runat="server" Text='<%# Eval("Column3") %>' />
                </td>
                <td>
                    <asp:Label ID="Label6" runat="server" Text='<%# Eval("Column4") %>' />
                </td>
            </tr>
        </ItemTemplate>
        <LayoutTemplate>
            <table id="Table2" runat="server">
                <tr id="Tr1" runat="server">
                    <td id="Td1" runat="server">
                        <table id="itemPlaceholderContainer" runat="server" border="0" style="">
                            <tr id="Tr2" runat="server" style="">
                                <th id="Th1" runat="server">Action</th>
                                <th id="Th2" runat="server">Id</th>
                                <th id="Th3" runat="server">First Name</th>
                                <th id="Th4" runat="server">Last Name</th>
                                <th id="Th5" runat="server">Column3 Name</th>
                                <th id="Th6" runat="server">Column4 Name</th>
                            </tr>
                            <tr id="itemPlaceholder" runat="server">
                            </tr>
                        </table>
                    </td>
                </tr>
            </table>
            <table width="900" align="center" style="text-align: center;">
                <tr id="Tr3" runat="server">
                    <td id="Td2" runat="server" style="">
                        <asp:DataPager ID="DataPager1" runat="server">
                            <Fields>
                                <asp:NextPreviousPagerField ButtonType="Link" ShowFirstPageButton="True" 
                                    ShowNextPageButton="False" ShowPreviousPageButton="False" />
                                <asp:NumericPagerField />
                                <asp:NextPreviousPagerField ButtonType="Link" ShowLastPageButton="True" 
                                    ShowNextPageButton="False" ShowPreviousPageButton="False" />
                            </Fields>
                        </asp:DataPager>
                    </td>
                </tr>
            </table>
        </LayoutTemplate>
        <SelectedItemTemplate>
                <tr style="">
                    <td>
                        <asp:LinkButton ID="LinkButton4" runat="server" CommandName="Delete" Text="Delete" 
                            CausesValidation="false" />
                        <asp:LinkButton ID="LinkButton5" runat="server" CommandName="Edit" Text="Edit" 
                            CausesValidation="false" />
                    </td>
                    <td>
                        <asp:Label ID="Label7" runat="server" Text='<%# Eval("Id") %>' />
                    </td>
                    <td>
                        <asp:Label ID="Label8" runat="server" Text='<%# Eval("FirstName") %>' />
                    </td>
                    <td>
                        <asp:Label ID="Label9" runat="server" Text='<%# Eval("LastName") %>' />
                    </td>
                    <td>
                        <asp:Label ID="Label10" runat="server" Text='<%# Eval("Column3") %>' />
                    </td>
                    <td>
                        <asp:Label ID="Label11" runat="server" Text='<%# Eval("Column4") %>' />
                    </td>
                </tr>
            </SelectedItemTemplate>
        </asp:ListView>
    </ContentTemplate>
</asp:updatepanel>

下面是代码背后的代码：


        protected void Page_Load(object sender, EventArgs e)
        {
            try
            {
                if (!IsPostBack)
                {
            LoadListView();
        }
        }


    private void LoadListView()
        {
            try
            {
                 List lstDetails = Session["ListView1Data"] as List;
           ListView1.DataSource = lstDetails;
                ListView1.DataBind();
                Session["ListView1Data"] = lstDetails ;
            }
            catch (Exception ex)
            {
                ExceptionLogger.LogException(ex);
            }
        }


    protected void ListView1_ItemDeleting(object sender, ListViewDeleteEventArgs e)
        {
            List lstDetails = Session["ListView1Data"] as List;
            int id = Convert.ToInt32(e.Values["Id"]);
            if (lstDetails.Exists(x => x.Id == id))
            {
                var tableDetail = lstDetails.Where(x => x.Id == id).FirstOrDefault();
                lstDetails.Remove(tableDetail);
                hdnListDeleteIds.Value = id + "|";
                ListView1.DataSource = lstDetails;
                ListView1.DataBind();
                ListView1.EditIndex = -1;
            }
        }
        protected void ListView1_ItemUpdating(object sender, ListViewUpdateEventArgs e)
        {
            List lstDetails = Session["ListView1Data"] as List;
            int id = Convert.ToInt32(e.OldValues["Id"]);
            if (lstDetails.Exists(x => x.Id == id))
            {
                var tableDetail = lstDetails.Where(x => x.Id == id).FirstOrDefault();
                tableDetail.FirstName = e.NewValues["FirstName"].ToString();
                tableDetail.LastName = e.NewValues["LastName"].ToString();
                tableDetail.Column3 = e.NewValues["Column3"].ToString();
                tableDetail.Column4 = Convert.ToDateTime(e.NewValues["Column4"]);
                hdnListUpdateIds.Value = id + "|";
                ListView1.DataSource = lstDetails;
                ListView1.DataBind();
                ListView1.EditIndex = -1;
                Session["ListView1Data"] = lstDetails;
            }
        }
        protected void ListView1_ItemInserting(object sender, ListViewInsertEventArgs e)
        {
            List lstDetails = Session["ListView1Data"] as List;

            EntityFrameworkModel.TableDetails tableDetail = new EntityFrameworkModel.TableDetails()
            {
                FirstName = e.Values["FirstName"].ToString(),
                LastName = e.Values["LastName"].ToString(),
                Column3 = e.Values["Column3"].ToString(),
                Column4 = Convert.ToDateTime(e.Values["Column4"]),
                Id = 0
            };
            lstDetails.Add(tableDetail);
            Session["ListView1Data"] = lstDetails;
            ListView1.DataSource = lstDetails;
            ListView1.DataBind();
            ListView1.EditIndex = -1;
        }
        protected void ListView1_ItemCanceling(object sender, ListViewCancelEventArgs e)
        {
            List lstDetails = Session["ListView1Data"] as List;
            ListView1.DataSource = lstDetails;
            ListView1.DataBind();
            e.Cancel = true;
            ListView1.EditIndex = -1;
        }
        protected void ListView1_ItemEditing(object sender, ListViewEditEventArgs e)
        {
            ListView1.EditIndex = e.NewEditIndex;
        }

我究竟做错了什么？请帮忙。

非常感谢

score 0 · Accepted Answer

我已将您的代码修改为一次性插入/更新/删除数据。希望它会帮助你。

编辑时需要再次绑定数据，

protected void ListView1_ItemEditing(object sender, ListViewEditEventArgs e)
{
    ListView1.EditIndex = e.NewEditIndex;
    BindData();
}

private void BindData()
{
    ListView1.DataSource = Session["ListView1Data"] as List<TableDetails>;
    ListView1.DataBind();
}

在删除项目时，您可以考虑将它们（仅现有项目，而不是新添加的）保留在单独的会话中。

protected void ListView1_ItemDeleting(object sender, ListViewDeleteEventArgs e)
{
    List<TableDetails> lstDetails = Session["ListView1Data"] as List<TableDetails>;

    if (lstDetails.Count >= e.ItemIndex + 1)
    {
        var tableDetail = lstDetails[e.ItemIndex];
        DeletedItems(tableDetail);
        lstDetails.Remove(tableDetail);
        ListView1.EditIndex = -1;
        Session["ListView1Data"] = lstDetails;
        BindData();
    }
}

private void DeletedItems(TableDetails tableDetail)
{
    List<TableDetails> lstDelItems = new List<TableDetails>();

    if (Session["DeletedItems"] != null)
    {
        lstDelItems = Session["DeletedItems"] as List<TableDetails>;
    }

    // No need to keep track of New Items(whose ID is 0)
    if (tableDetail.Id > 0)
    {
        lstDelItems.Add(tableDetail);
        Session["DeletedItems"] = lstDelItems;
    }
 }

现在，您的保存按钮单击事件可以是

protected void btnSave_Click(object sender, EventArgs e)
{
    List<TableDetails> lstDelItems = new List<TableDetails>();
    List<TableDetails> lstDetails = Session["ListView1Data"] as List<TableDetails>;
    EntityFrameworkModel entity = new EntityFrameworkModel();

    if (Session["DeletedItems"] != null)
    {
        lstDelItems = Session["DeletedItems"] as List<TableDetails>;
    }

    foreach (TableDetails det in lstDetails)
    {
        // Insert. For all the new entries, the ID value will be 0
        if (det.Id == 0)
        {
            entity.TableDetails.Add(det);                    
        }
        // Update. If ID exists in the db, its a modified data
        else if (entity.TableDetails.Any(d => d.Id == det.Id))
        {
            TableDetails detail = entity.TableDetails.First(d => d.Id == det.Id);
            detail.FirstName = det.FirstName;
            detail.LastName = det.LastName;
            detail.Column3 = det.Column3;
            detail.Column4 = det.Column4;
        }

        entity.SaveChanges();
    }

    // Delete.
    foreach (TableDetails det in lstDelItems)
    {
        TableDetails detail = entity.TableDetails.First(d => d.Id == det.Id);
        entity.TableDetails.Remove(detail);
        entity.SaveChanges();
    }

    LoadListView();
    Session["DeletedItems"] = null;
}

更新：

是的，您需要修改更新事件。由于您的所有新项目都将 0 作为您的 ID 值，因此您不能依赖它。你可以依靠RowIndex这个。

protected void ListView1_ItemUpdating(object sender, ListViewUpdateEventArgs e)
{
    List<TableDetails> lstDetails = Session["ListView1Data"] as List<TableDetails>;

    if (lstDetails.Count >= e.ItemIndex + 1)
    {
        var tableDetail = lstDetails[e.ItemIndex];
        tableDetail.FirstName = e.NewValues["FirstName"].ToString();
        tableDetail.LastName = e.NewValues["LastName"].ToString();
        tableDetail.Column3 = e.NewValues["Column3"].ToString();
        tableDetail.Column4 = Convert.ToDateTime(e.NewValues["Column4"]);             
        ListView1.EditIndex = -1;
        Session["ListView1Data"] = lstDetails;
        BindData();
    }
}

c# - 如何在 ASP:ListView 中一次批量实现所有插入、更新、删除操作

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