GridViewSortEventHandler (Delegado)
Ensamblado: System.Web (en system.web.dll)
/** @delegate */ public delegate void GridViewSortEventHandler ( Object sender, GridViewSortEventArgs e )
No aplicable.
Parámetros
- sender
Origen del evento.
- e
Objeto GridViewSortEventArgs que contiene los datos del evento.
El evento Sorting se produce al hacer clic en el hipervínculo que ordena una columna, pero antes de que el control GridView realice el tratamiento de la operación de ordenación. Esto permite proporcionar un método de control del evento que realiza una rutina personalizada, como cancelar la operación de ordenación, siempre que se produce este evento.
Cuando se crea un delegado GridViewSortEventHandler, se identifica el método que controlará el evento. Para asociar el evento al controlador del evento, se debe agregar al evento una instancia del delegado. Siempre que se produzca el evento, se llamará al controlador del evento, a menos que se elimine el delegado. Para obtener más información sobre los delegados de los controladores de eventos, vea Eventos y delegados.
El siguiente ejemplo muestra cómo agregar un delegado GridViewSortEventHandler mediante programación al evento Sorting de un control GridView.
<%@ 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"> void Page_Load(Object sender, EventArgs e) { // Create a new GridView object. GridView authorGridView = new GridView(); // Set the GridView object's properties. authorGridView.ID = "AuthorGridView"; authorGridView.DataSourceID = "AuthorsSqlDataSource"; authorGridView.AutoGenerateColumns = true; authorGridView.AllowSorting = true; // Programmatically register the event-handling methods. authorGridView.Sorting += new GridViewSortEventHandler(this.AuthorsGridView_Sorting); // Add the GridView object to the Controls collection // of the PlaceHolder control. GridViewPlaceHolder.Controls.Add(authorGridView); } void AuthorsGridView_Sorting(Object sender, GridViewSortEventArgs e) { // Cancel the sorting operation if the user attempts to sort // the Contract column. if(e.SortExpression == "contract") { e.Cancel = true; Message.Text = "You cannot sort the Contract column."; } else { // Clear the message label. Message.Text = ""; } } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>GridViewSortEventHandler Example</title> </head> <body> <form id="form1" runat="server"> <h3>GridViewSortEventHandler Example</h3> <asp:label id="Message" forecolor="Red" runat="server"/> <br/> <asp:placeholder id="GridViewPlaceHolder" runat="Server"/> <!-- This example uses Microsoft SQL Server and connects --> <!-- to the Pubs sample database. --> <asp:sqldatasource id="AuthorsSqlDataSource" selectcommand="SELECT [au_id], [au_lname], [au_fname], [address], [city], [state], [zip], [contract] FROM [authors]" updatecommand="UPDATE authors SET au_lname=@au_lname, au_fname=@au_fname, address=@address, city=@city, state=@state, zip=@zip, contract=@contract WHERE (authors.au_id = @au_id)" connectionstring="server=localhost;database=pubs;integrated security=SSPI" runat="server"> </asp:sqldatasource> </form> </body> </html>
El siguiente ejemplo muestra cómo agregar un delegado GridViewSortEventHandler mediante declaración al evento Sorting de un control GridView.
<%@ 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"> void CustomersGridView_Sorting(Object sender, GridViewSortEventArgs e) { // Cancel the sorting operation if the user attempts // to sort by address. if (e.SortExpression == "Address") { e.Cancel = true; Message.Text = "You cannot sort by address."; SortInformationLabel.Text = ""; } else { Message.Text = ""; } } void CustomersGridView_Sorted(Object sender, EventArgs e) { // Display the sort expression and sort direction. SortInformationLabel.Text = "Sorting by " + CustomersGridView.SortExpression.ToString() + " in " + CustomersGridView.SortDirection.ToString() + " order."; } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head runat="server"> <title>GridView Sorting Example</title> </head> <body> <form id="form1" runat="server"> <h3>GridView Sorting Example</h3> <asp:label id="Message" forecolor="Red" runat="server"/> <br/> <asp:label id="SortInformationLabel" forecolor="Navy" runat="server"/> <br/> <asp:gridview id="CustomersGridView" datasourceid="CustomersSource" autogeneratecolumns="true" allowpaging="true" emptydatatext="No data available." allowsorting="true" onsorting="CustomersGridView_Sorting" onsorted="CustomersGridView_Sorted" runat="server"> </asp:gridview> <!-- This example uses Microsoft SQL Server and connects --> <!-- to the Northwind sample database. Use an ASP.NET --> <!-- expression to retrieve the connection string value --> <!-- from the Web.config file. --> <asp:sqldatasource id="CustomersSource" selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]" connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" runat="server"/> </form> </body> </html>
Windows 98, Windows 2000 Service Pack 4, Windows CE, Windows Millennium, Windows Mobile para Pocket PC, Windows Mobile para Smartphone, Windows Server 2003, Windows XP Media Center, Windows XP Professional x64, Windows XP SP2, Windows XP Starter
Microsoft .NET Framework 3.0 es compatible con Windows Vista, Microsoft Windows XP SP2 y Windows Server 2003 SP1.