DetailsViewDeletedEventHandler Delegado
Definición
Importante
Parte de la información hace referencia a la versión preliminar del producto, que puede haberse modificado sustancialmente antes de lanzar la versión definitiva. Microsoft no otorga ninguna garantía, explícita o implícita, con respecto a la información proporcionada aquí.
Representa el método que controla el evento ItemDeleted de un control DetailsView.
public delegate void DetailsViewDeletedEventHandler(System::Object ^ sender, DetailsViewDeletedEventArgs ^ e);
public delegate void DetailsViewDeletedEventHandler(object sender, DetailsViewDeletedEventArgs e);
type DetailsViewDeletedEventHandler = delegate of obj * DetailsViewDeletedEventArgs -> unit
Public Delegate Sub DetailsViewDeletedEventHandler(sender As Object, e As DetailsViewDeletedEventArgs)
Parámetros
- sender
- Object
Origen del evento.
Objeto DetailsViewDeletedEventArgs que contiene los datos del evento.
Ejemplos
En el ejemplo de código siguiente se muestra cómo agregar mediante programación un DetailsViewDeletedEventHandler delegado al ItemDeleted evento de un DetailsView control .
<%@ page language="C#"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
// Create a new DetailsView object.
DetailsView customerDetailsView = new DetailsView();
// Set the DetailsView object's properties.
customerDetailsView.ID = "CustomerDetailsView";
customerDetailsView.DataSourceID = "DetailsViewSource";
customerDetailsView.AutoGenerateRows = true;
customerDetailsView.AutoGenerateDeleteButton = true;
customerDetailsView.AllowPaging = true;
customerDetailsView.PagerSettings.Mode =
PagerButtons.NextPrevious;
customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };
// Programmatically register the event-handling method
// for the ItemDeleted event of a DetailsView control.
customerDetailsView.ItemDeleted +=
new DetailsViewDeletedEventHandler(
this.CustomerDetailView_ItemDeleted);
// Add the DetailsView object to the Controls collection
// of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView);
}
void CustomerDetailView_ItemDeleted(Object sender,
DetailsViewDeletedEventArgs e)
{
// Use the Exception property to determine whether an exception
// occurred during the delete operation.
if (e.Exception == null)
{
// Use the AffectedRows property to determine the numbers of
// rows affected by the delete operation.
if (e.AffectedRows == 1)
{
MessageLabel.Text = e.AffectedRows.ToString()
+ " record deleted successfully.";
}
else
{
MessageLabel.Text = e.AffectedRows.ToString()
+ " records deleted successfully.";
}
}
else
{
// Insert the code to handle the exception.
MessageLabel.Text = e.Exception.Message;
// Use the ExceptionHandled property to indicate that the
// exception is already handled.
e.ExceptionHandled = true;
}
}
</script>
<head runat="server">
<title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewDeletedEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:PlaceHolder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- 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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
deletecommand="Delete [Customers]
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ page language="VB"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Create a new DetailsView object.
Dim customerDetailsView As New DetailsView()
' Set the DetailsView object's properties.
customerDetailsView.ID = "CustomerDetailsView"
customerDetailsView.DataSourceID = "DetailsViewSource"
customerDetailsView.AutoGenerateRows = True
customerDetailsView.AutoGenerateDeleteButton = True
customerDetailsView.AllowPaging = True
customerDetailsView.PagerSettings.Mode = _
PagerButtons.NextPrevious
Dim keyArray() As String = {"CustomerID"}
customerDetailsView.DataKeyNames = keyArray
' Programmatically register the event-handling method
' for the ItemDeleted event of a DetailsView control.
AddHandler customerDetailsView.ItemDeleted, _
AddressOf CustomerDetailView_ItemDeleted
' Add the DetailsView object to the Controls collection
' of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView)
End Sub
Sub CustomerDetailView_ItemDeleted(ByVal sender As Object, _
ByVal e As DetailsViewDeletedEventArgs)
' Use the Exception property to determine whether an exception
' occurred during the delete operation.
If e.Exception Is Nothing Then
' Use the AffectedRows property to determine the numbers of
' rows affected by the delete operation.
If e.AffectedRows = 1 Then
MessageLabel.Text = e.AffectedRows.ToString() _
& " record deleted successfully."
Else
MessageLabel.Text = e.AffectedRows.ToString() _
& " records deleted successfully."
End If
Else
' Insert the code to handle the exception.
MessageLabel.Text = e.Exception.Message
' Use the ExceptionHandled property to indicate that the
' exception is already handled.
e.ExceptionHandled = True
End If
End Sub
</script>
<head runat="server">
<title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewDeletedEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:PlaceHolder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- 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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
deletecommand="Delete [Customers]
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
En el ejemplo de código siguiente se muestra cómo agregar mediante declaración un DetailsViewDeletedEventHandler delegado al ItemDeleted evento de un DetailsView control.
<%@ page language="C#"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
void CustomerDetailView_ItemDeleted(Object sender,
DetailsViewDeletedEventArgs e)
{
// Use the Exception property to determine whether an exception
// occurred during the delete operation.
if (e.Exception == null)
{
// Use the AffectedRows property to determine the numbers of
// rows affected by the delete operation.
if (e.AffectedRows == 1)
{
MessageLabel.Text = e.AffectedRows.ToString()
+ " record deleted successfully.";
}
else
{
MessageLabel.Text = e.AffectedRows.ToString()
+ " records deleted successfully.";
}
}
else
{
// Insert the code to handle the exception.
MessageLabel.Text = e.Exception.Message;
// Use the ExceptionHandled property to indicate that the
// exception is already handled.
e.ExceptionHandled = true;
}
}
</script>
<head runat="server">
<title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewDeletedEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
autogeneraterows="true"
autogeneratedeletebutton="true"
allowpaging="true"
datakeynames="CustomerID"
runat="server">
<pagersettings mode="NextPrevious"/>
</asp:detailsview>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- 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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
deletecommand="Delete [Customers]
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ page language="VB"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script runat="server">
Sub CustomerDetailView_ItemDeleted(ByVal sender As Object, _
ByVal e As DetailsViewDeletedEventArgs)
' Use the Exception property to determine whether an exception
' occurred during the delete operation.
If e.Exception Is Nothing Then
' Use the AffectedRows property to determine the numbers of
' rows affected by the delete operation.
If e.AffectedRows = 1 Then
MessageLabel.Text = e.AffectedRows.ToString() _
& " record deleted successfully."
Else
MessageLabel.Text = e.AffectedRows.ToString() _
& " records deleted successfully."
End If
Else
' Insert the code to handle the exception.
MessageLabel.Text = e.Exception.Message
' Use the ExceptionHandled property to indicate that the
' exception is already handled.
e.ExceptionHandled = True
End If
End Sub
</script>
<head runat="server">
<title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewDeletedEventHandler Example</h3>
<asp:detailsview id="CustomerDetailsView"
datasourceid="DetailsViewSource"
autogeneraterows="true"
autogeneratedeletebutton="true"
allowpaging="true"
datakeynames="CustomerID"
runat="server">
<pagersettings mode="NextPrevious"/>
</asp:detailsview>
<br/><br/>
<asp:label id="MessageLabel"
forecolor="Red"
runat="server"/>
<!-- 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="DetailsViewSource"
selectcommand="Select [CustomerID], [CompanyName], [Address],
[City], [PostalCode], [Country] From [Customers]"
deletecommand="Delete [Customers]
Where [CustomerID]=@CustomerID"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
Comentarios
El DetailsView control genera el ItemDeleted evento cuando se hace clic en un botón Eliminar (un botón con su CommandName
propiedad establecida en "Eliminar") dentro del control, pero después de que el DetailsView control elimine el registro. Esto permite proporcionar un controlador de eventos que realice una rutina personalizada, como comprobar los resultados de una operación de eliminación, siempre que se produzca este evento.
Cuando se crea un delegado DetailsViewDeletedEventHandler, se identifica el método que controlará el evento. Para asociar el evento al controlador, se debe agregar una instancia del delegado al evento. Siempre que se produce el evento, se llama a su controlador, a menos que se quite el delegado. Para obtener más información sobre los delegados del controlador de eventos, vea Control y generación de eventos.
Métodos de extensión
GetMethodInfo(Delegate) |
Obtiene un objeto que representa el método representado por el delegado especificado. |