DetailsViewCommandEventHandler Delegar
Definição
Importante
Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.
Representa o método que manipula o evento ItemCommand de um controle DetailsView.
public delegate void DetailsViewCommandEventHandler(System::Object ^ sender, DetailsViewCommandEventArgs ^ e);public delegate void DetailsViewCommandEventHandler(object sender, DetailsViewCommandEventArgs e);type DetailsViewCommandEventHandler = delegate of obj * DetailsViewCommandEventArgs -> unitPublic Delegate Sub DetailsViewCommandEventHandler(sender As Object, e As DetailsViewCommandEventArgs)Parâmetros
- sender
- Object
A fonte do evento.
Um DetailsViewCommandEventArgs que contém os dados do evento.
Exemplos
O exemplo de código a seguir demonstra como adicionar programaticamente um DetailsViewCommandEventHandler delegado ao ItemCommand evento de um DetailsView controle . Este exemplo usa o modelo de codificação de arquivo único.
<%@ 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 DetailsView object.
DetailsView customerDetailsView = new DetailsView();
// Set the DetailsView object's properties.
customerDetailsView.ID = "CustomerDetailsView";
customerDetailsView.DataSourceID = "DetailsViewSource";
customerDetailsView.AutoGenerateRows = true;
customerDetailsView.AllowPaging = true;
customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };
// Add a button field to the DetailsView control.
ButtonField field = new ButtonField();
field.ButtonType = ButtonType.Link;
field.CausesValidation = false;
field.Text = "Add to List";
field.CommandName="Add";
customerDetailsView.Fields.Add(field);
// Programmatically register the event-handling method
// for the ItemDeleting event of a DetailsView control.
customerDetailsView.ItemCommand
+= new DetailsViewCommandEventHandler(
this.CustomerDetailsView_ItemCommand);
// Add the DetailsView object to the Controls collection
// of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView);
}
void CustomerDetailsView_ItemCommand(Object sender,
DetailsViewCommandEventArgs e)
{
// Use the CommandName property to determine which button
// was clicked.
if (e.CommandName == "Add")
{
// Get the DetailsView control that raised the event.
DetailsView customerDetailsView = (DetailsView)e.CommandSource;
// Add the current customer to the customer list.
// Get the row that contains the company name. In this
// example, the company name is in the second row (index 1)
// of the DetailsView control.
DetailsViewRow row = customerDetailsView.Rows[1];
// Get the company's name from the appropriate cell.
// In this example, the company name is in the second cell
// (index 1) of the row.
String name = row.Cells[1].Text;
// Create a ListItem object with the company name.
ListItem item = new ListItem(name);
// Add the ListItem object to the ListBox, if the
// item doesn't already exist.
if (!CustomerListBox.Items.Contains(item))
{
CustomerListBox.Items.Add(item);
}
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewCommandEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:placeholder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
Selected Customers:<br/>
<asp:listbox id="CustomerListBox"
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]"
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">
<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.AllowPaging = True
Dim keyArray() As String = {"CustomerID"}
customerDetailsView.DataKeyNames = keyArray
' Add a button field to the DetailsView control.
Dim field As New ButtonField()
field.ButtonType = ButtonType.Link
field.CausesValidation = False
field.Text = "Add to List"
field.CommandName = "Add"
customerDetailsView.Fields.Add(field)
' Programmatically register the event-handling method
' for the ItemDeleting event of a DetailsView control.
AddHandler customerDetailsView.ItemCommand, _
AddressOf CustomerDetailsView_ItemCommand
' Add the DetailsView object to the Controls collection
' of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView)
End Sub
Sub CustomerDetailsView_ItemCommand(ByVal sender As Object, _
ByVal e As DetailsViewCommandEventArgs)
' Use the CommandName property to determine which button
' was clicked.
If e.CommandName = "Add" Then
' Get the DetailsView control that raised the event.
Dim customerDetailsView As DetailsView = _
CType(e.CommandSource, DetailsView)
' Add the current customer to the customer list.
' Get the row that contains the company name. In this
' example, the company name is in the second row (index 1)
' of the DetailsView control.
Dim row As DetailsViewRow = customerDetailsView.Rows(1)
' Get the company's name from the appropriate cell.
' In this example, the company name is in the second cell
' (index 1) of the row.
Dim name As String = row.Cells(1).Text
' Create a ListItem object with the company name.
Dim item As New ListItem(name)
' Add the ListItem object to the ListBox, if the
' item doesn't already exist.
If Not CustomerListBox.Items.Contains(item) Then
CustomerListBox.Items.Add(item)
End If
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
<form id="form1" runat="server">
<h3>DetailsViewCommandEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:placeholder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
Selected Customers:<br/>
<asp:listbox id="CustomerListBox"
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]"
connectionstring=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
O exemplo de código a seguir mostra uma versão do modelo de codificação code-behind do exemplo anterior. Para que este exemplo funcione, você deve copiar o código abaixo para o arquivo code-behind associado.
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!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" >
<head runat="server">
<title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>DetailsViewCommandEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:placeholder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
Selected Customers:<br/>
<asp:listbox id="CustomerListBox"
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]"
connectionstring="
<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="false" CodeFile="DefaultVB.aspx.vb" Inherits="DefaultVB" %>
<!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" >
<head runat="server">
<title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>DetailsViewCommandEventHandler Example</h3>
<!-- Use a PlaceHolder control as the container for the -->
<!-- dynamically generated DetailsView control. -->
<asp:placeholder id="DetailsViewPlaceHolder"
runat="server"/>
<br/><br/>
Selected Customers:<br/>
<asp:listbox id="CustomerListBox"
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]"
connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
runat="server"/>
</form>
</body>
</html>
O exemplo de código a seguir mostra o arquivo code-behind do exemplo anterior.
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class _Default : System.Web.UI.Page
{
protected 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.AllowPaging = true;
customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };
// Add a button field to the DetailsView control.
ButtonField field = new ButtonField();
field.ButtonType = ButtonType.Link;
field.CausesValidation = false;
field.Text = "Add to List";
field.CommandName = "Add";
customerDetailsView.Fields.Add(field);
// Programmatically register the event-handling method
// for the ItemDeleting event of a DetailsView control.
customerDetailsView.ItemCommand += new DetailsViewCommandEventHandler(this.CustomerDetailsView_ItemCommand);
// Add the DetailsView object to the Controls collection
// of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView);
}
void CustomerDetailsView_ItemCommand(Object sender, DetailsViewCommandEventArgs e)
{
// Use the CommandName property to determine which button
// was clicked.
if (e.CommandName == "Add")
{
// Get the DetailsView control that raised the event.
DetailsView customerDetailsView = (DetailsView)sender;
// Add the current customer to the customer list.
// Get the row that contains the company name. In this
// example, the company name is in the second row (index 1)
// of the DetailsView control.
DetailsViewRow row = customerDetailsView.Rows[1];
// Get the company's name from the appropriate cell.
// In this example, the company name is in the second cell
// (index 1) of the row.
String name = row.Cells[1].Text;
// Create a ListItem object with the company name.
ListItem item = new ListItem(name);
// Add the ListItem object to the ListBox, if the
// item doesn't already exist.
if (!CustomerListBox.Items.Contains(item))
{
CustomerListBox.Items.Add(item);
}
}
}
}
Partial Class DefaultVB
Inherits System.Web.UI.Page
Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
' 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.AllowPaging = True
Dim keyArray() As String = {"CustomerID"}
customerDetailsView.DataKeyNames = keyArray
' Add a button field to the DetailsView control.
Dim field As New ButtonField()
field.ButtonType = ButtonType.Link
field.CausesValidation = False
field.Text = "Add to List"
field.CommandName = "Add"
customerDetailsView.Fields.Add(field)
' Programmatically register the event-handling method
' for the ItemDeleting event of a DetailsView control.
AddHandler customerDetailsView.ItemCommand, AddressOf CustomerDetailsView_ItemCommand
' Add the DetailsView object to the Controls collection
' of the PlaceHolder control.
DetailsViewPlaceHolder.Controls.Add(customerDetailsView)
End Sub
Sub CustomerDetailsView_ItemCommand(ByVal sender As Object, ByVal e As DetailsViewCommandEventArgs)
' Use the CommandName property to determine which button
' was clicked.
If e.CommandName = "Add" Then
' Get the DetailsView control that raised the event.
Dim customerDetailsView As DetailsView = CType(sender, DetailsView)
' Add the current customer to the customer list.
' Get the row that contains the company name. In this
' example, the company name is in the second row (index 1)
' of the DetailsView control.
Dim row As DetailsViewRow = customerDetailsView.Rows(1)
' Get the company's name from the appropriate cell.
' In this example, the company name is in the second cell
' (index 1) of the row.
Dim name As String = row.Cells(1).Text
' Create a ListItem object with the company name.
Dim item As New ListItem(name)
' Add the ListItem object to the ListBox, if the
' item doesn't already exist.
If Not CustomerListBox.Items.Contains(item) Then
CustomerListBox.Items.Add(item)
End If
End If
End Sub
End Class
O exemplo de código a seguir demonstra como adicionar declarativamente um DetailsViewCommandEventHandler delegado ao ItemCommand evento de um DetailsView controle.
<%@ 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 CustomerDetailView_ItemCommand(Object sender, DetailsViewCommandEventArgs e)
{
// Use the CommandName property to determine which button
// was clicked.
if (e.CommandName == "Add")
{
// Add the current store to the contact list.
// Get the row that contains the store name. In this
// example, the store name is in the second row (index 1)
// of the DetailsView control.
DetailsViewRow row = CustomerDetailView.Rows[1];
// Get the store's name from the appropriate cell.
// In this example, the store name is in the second cell
// (index 1) of the row.
String name = row.Cells[1].Text;
// Create a ListItem object with the store's name.
ListItem item = new ListItem(name);
// Add the ListItem object to the ListBox, if the
// item doesn't already exist.
if (!ContactListBox.Items.Contains(item))
{
ContactListBox.Items.Add(item);
}
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>
DetailsView ItemCommand Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>
DetailsView ItemCommand Example</h3>
<asp:DetailsView ID="CustomerDetailView"
DataSourceID="DetailsViewSource"
AutoGenerateRows="false"
DataKeyNames="CustomerID"
AllowPaging="true"
OnItemCommand="CustomerDetailView_ItemCommand"
runat="server">
<FieldHeaderStyle BackColor="Navy" ForeColor="White" />
<Fields>
<asp:BoundField DataField="CustomerID" HeaderText="Store ID" />
<asp:BoundField DataField="CompanyName" HeaderText="Store Name" />
<asp:BoundField DataField="City" HeaderText="City" />
<asp:ButtonField CommandName="Add" Text="Add Contact" />
</Fields>
</asp:DetailsView>
<hr />
Contacts:<br />
<asp:ListBox ID="ContactListBox" 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" runat="server"
ConnectionString=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
InsertCommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
SelectCommand="Select [CustomerID], [CompanyName],
[Address], [City], [PostalCode], [Country] From
[Customers]">
</asp:SqlDataSource>
</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">
<script runat="server">
Sub CustomerDetailView_ItemCommand(ByVal sender As Object, ByVal e As DetailsViewCommandEventArgs)
' Use the CommandName property to determine which button
' was clicked.
If e.CommandName = "Add" Then
' Add the current store to the contact list.
' Get the row that contains the store name. In this
' example, the store name is in the second row (index 1)
' of the DetailsView control.
Dim row As DetailsViewRow = CustomerDetailView.Rows(1)
' Get the store's name from the appropriate cell.
' In this example, the store name is in the second cell
' (index 1) of the row.
Dim name As String = row.Cells(1).Text
' Create a ListItem object with the store's name.
Dim item As New ListItem(name)
' Add the ListItem object to the ListBox, if the
' item doesn't already exist.
If Not ContactListBox.Items.Contains(item) Then
ContactListBox.Items.Add(item)
End If
End If
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>
DetailsView ItemCommand Example</title>
</head>
<body>
<form id="Form1" runat="server">
<h3>
DetailsView ItemCommand Example</h3>
<asp:DetailsView ID="CustomerDetailView"
DataSourceID="DetailsViewSource"
AutoGenerateRows="false"
DataKeyNames="CustomerID"
AllowPaging="true"
OnItemCommand="CustomerDetailView_ItemCommand"
runat="server">
<FieldHeaderStyle BackColor="Navy" ForeColor="White" />
<Fields>
<asp:BoundField DataField="CustomerID" HeaderText="Store ID" />
<asp:BoundField DataField="CompanyName" HeaderText="Store Name" />
<asp:BoundField DataField="City" HeaderText="City" />
<asp:ButtonField CommandName="Add" Text="Add Contact" />
</Fields>
</asp:DetailsView>
<hr />
Contacts:<br />
<asp:ListBox ID="ContactListBox" 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" runat="server"
ConnectionString=
"<%$ ConnectionStrings:NorthWindConnectionString%>"
InsertCommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
SelectCommand="Select [CustomerID], [CompanyName],
[Address], [City], [PostalCode], [Country] From
[Customers]">
</asp:SqlDataSource>
</form>
</body>
</html>
Comentários
O DetailsView controle aciona o ItemCommand evento quando um botão dentro de um ButtonFieldcampo de linha , CommandFieldou TemplateField é clicado. Isso permite que você forneça um manipulador de eventos que executa uma rotina personalizada sempre que esse evento ocorre.
Observação
O DetailsView controle também gera outros eventos especializados quando determinados botões são clicados (botões com a CommandName propriedade definida como "Excluir", "Inserir", "Página" ou "Atualizar"). Ao usar um desses botões, você deve considerar o uso de um dos eventos especializados fornecidos pelo controle (como ItemDeleted ou ItemDeleting).
Ao criar um DetailsViewCommandEventHandler delegado, você identifica o método que manipulará o evento. Para associar o evento ao manipulador de eventos, adicione uma instância do delegado ao evento. O manipulador de eventos é chamado sempre que o evento ocorre, a menos que você remova o representante. Para obter mais informações sobre delegados do manipulador de eventos, consulte Manipulando e gerando eventos.
Métodos de Extensão
| GetMethodInfo(Delegate) |
Obtém um objeto que representa o método representado pelo delegado especificado. |
Aplica-se a
Confira também
Colaborar conosco no GitHub
A fonte deste conteúdo pode ser encontrada no GitHub, onde você também pode criar e revisar problemas e solicitações de pull. Para obter mais informações, confira o nosso guia para colaboradores.
