ListViewDeleteEventArgs Class
Provides data for the ItemDeleting event.
Assembly: System.Web.Extensions (in System.Web.Extensions.dll)
The ListView control raises the ItemDeleting event when a Delete button is clicked or the DeleteItem method is called, but before the ListView control deletes the item. (A Delete button is one whose CommandName property is set to "Delete".) This enables you to provide an event-handling method that performs a custom routine whenever this event occurs, such as canceling the delete operation.
A ListViewDeleteEventArgs object is passed to the event-handling method, which enables you to determine the index of the item that is being deleted. You can also cancel the delete operation. To do so, set the Cancel property of the ListViewDeleteEventArgs object to true. If necessary, you can also work with the Keys and Values collections before the values are passed to the data source.
For a list of initial property values for an instance of ListViewDeleteEventArgs, see the ListViewDeleteEventArgs constructor.
The following example shows how to use the ListViewDeleteEventArgs object to cancel the delete operation if the user tries to remove the last item from a ListView control.
<%@ Page language="C#" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> protected void CategoriesListView_OnItemDeleting(object sender, ListViewDeleteEventArgs e) { if (SubCategoriesGridView.Rows.Count > 0) { MessageLabel.Text = "You cannot delete a category that has sub-categories."; e.Cancel = true; } } protected void Page_Load() { MessageLabel.Text = String.Empty; } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head id="Head1" runat="server"> <title>Subcategories List</title> </head> <body> <form id="form1" runat="server"> <b>Categories</b> <br /> <asp:Label ForeColor="Red" runat="server" ID="MessageLabel" /><br /> <asp:ListView runat="server" ID="CategoriesListView" OnItemDeleting="CategoriesListView_OnItemDeleting" DataSourceID="CategoriesDataSource" DataKeyNames="ProductCategoryID"> <LayoutTemplate> <table runat="server" id="tblCategories" cellspacing="0" cellpadding="1" width="440px" border="1"> <tr id="itemPlaceholder" runat="server"></tr> </table> </LayoutTemplate> <ItemTemplate> <tr runat="server"> <td> <asp:Label runat="server" ID="NameLabel" Text='<%#Eval("Name") %>' /> </td> <td style="width:40px"> <asp:LinkButton runat="server" ID="SelectCategoryButton" Text="Select" CommandName="Select" /> </td> </tr> </ItemTemplate> <SelectedItemTemplate> <tr runat="server" style="background-color:#90EE90"> <td> <asp:Label runat="server" ID="NameLabel" Text='<%#Eval("Name") %>' /> </td> <td style="width:40px"> <asp:LinkButton runat="server" ID="SelectCategoryButton" Text="Delete" CommandName="Delete" /> </td> </tr> </SelectedItemTemplate> </asp:ListView> <br /> <b>Subcategories</b> <asp:GridView runat="server" ID="SubCategoriesGridView" Width="300px" DataSourceID="SubCategoriesDataSource" DataKeyNames="ProductSubcategoryID" AutoGenerateColumns="True" /> <!-- This example uses Microsoft SQL Server and connects --> <!-- to the AdventureWorks sample database. Use an ASP.NET --> <!-- expression to retrieve the connection string value --> <!-- from the Web.config file. --> <asp:SqlDataSource ID="CategoriesDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>" SelectCommand="SELECT [ProductCategoryID], [Name] FROM Production.ProductCategory"> </asp:SqlDataSource> <asp:SqlDataSource ID="SubCategoriesDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>" SelectCommand="SELECT [ProductSubcategoryID], [Name] FROM Production.ProductSubcategory WHERE ProductCategoryID = @ProductCategoryID ORDER BY [Name]"> <SelectParameters> <asp:ControlParameter Name="ProductCategoryID" DefaultValue="0" ControlID="CategoriesListView" PropertyName="SelectedValue" /> </SelectParameters> </asp:SqlDataSource> </form> </body> </html>
- AspNetHostingPermission
For operating in a hosted environment. Demand value: LinkDemand; Permission value: Minimal
- AspNetHostingPermission
For operating in a hosted environment. Demand value: InheritanceDemand; Permission value: Minimal
System.EventArgs
System.ComponentModel.CancelEventArgs
System.Web.UI.WebControls.ListViewDeleteEventArgs
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.