DetailsViewCommandEventHandler Делегат
Определение
Важно!
Некоторые сведения относятся к предварительной версии продукта, в которую до выпуска могут быть внесены существенные изменения. Майкрософт не предоставляет никаких гарантий, явных или подразумеваемых, относительно приведенных здесь сведений.
Представляет метод, обрабатывающий ItemCommand событие DetailsView элемента управления.
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)Параметры
- sender
- Object
Источник события.
Объект, DetailsViewCommandEventArgs содержащий данные события.
Примеры
В следующем примере кода показано, как программно добавить DetailsViewCommandEventHandler делегат в ItemCommand событие DetailsView элемента управления. В этом примере используется модель программирования с одним файлом.
<%@ 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>
В следующем примере кода показана версия модели кодирования программной части предыдущего примера. Чтобы этот пример работал, необходимо скопировать приведенный ниже код в связанный файл программной части.
<%@ 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>
В следующем примере кода показан файл программной части для предыдущего примера.
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
В следующем примере кода показано, как декларативно добавить DetailsViewCommandEventHandler делегат в ItemCommand событие DetailsView элемента управления.
<%@ 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>
Комментарии
Элемент DetailsView управления вызывает ItemCommand событие при нажатии кнопки в ButtonFieldCommandFieldполе строки или TemplateField кнопки. Это позволяет предоставить обработчик событий, выполняющий настраиваемую подпрограмму при каждом возникновении этого события.
Note
Элемент DetailsView управления также вызывает другие специализированные события, когда некоторые кнопки щелкаются (кнопки со CommandName свойством, заданным значением "Удалить", "Вставка", "Страница" или "Обновить"). При использовании одной из этих кнопок следует рассмотреть возможность использования одного из специализированных событий, предоставляемых элементом управления (например ItemDeleted , или ItemDeleting).
При создании делегата DetailsViewCommandEventHandler вы определите метод, который будет обрабатывать событие. Чтобы связать событие с обработчиком событий, добавьте экземпляр делегата в событие. Обработчик событий вызывается всякий раз, когда происходит событие, если вы не удалите делегат. Дополнительные сведения о делегатах обработчика событий см. в разделе "Обработка и создание событий".
Методы расширения
| Имя | Описание |
|---|---|
| GetMethodInfo(Delegate) |
Возвращает объект, представляющий метод, представленный указанным делегатом. |
