ListViewCommandEventArgs Classe

Definizione

Fornisce i dati per l'evento ItemCommand.Provides data for the ItemCommand event.

public ref class ListViewCommandEventArgs : System::Web::UI::WebControls::CommandEventArgs
public class ListViewCommandEventArgs : System.Web.UI.WebControls.CommandEventArgs
type ListViewCommandEventArgs = class
    inherit CommandEventArgs
Public Class ListViewCommandEventArgs
Inherits CommandEventArgs
Ereditarietà
ListViewCommandEventArgs

Esempio

Nell'esempio seguente viene illustrato come utilizzare l'oggetto ListViewCommandEventArgs passato al gestore eventi.The following example shows how to use the ListViewCommandEventArgs object that is passed to the event handler.

<%@ 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 EmployeesListView_OnItemCommand(object sender, ListViewCommandEventArgs e)
  {
    if (String.Equals(e.CommandName, "AddToList"))
    {
      // Verify that the employee ID is not already in the list. If not, add the
      // employee to the list.
      ListViewDataItem dataItem = (ListViewDataItem)e.Item;
      string employeeID = 
        EmployeesListView.DataKeys[dataItem.DisplayIndex].Value.ToString();
      
      if (SelectedEmployeesListBox.Items.FindByValue(employeeID) == null)
      {
        ListItem item = new ListItem(e.CommandArgument.ToString(), employeeID);
        SelectedEmployeesListBox.Items.Add(item);
      }
    }
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Employee List</title>
  </head>
  <body>
    <form id="form1" runat="server">
      <asp:ListView runat="server" 
        ID="EmployeesListView"
        OnItemCommand="EmployeesListView_OnItemCommand"
        DataSourceID="EmployeesDataSource" 
        DataKeyNames="EmployeeID">
        <LayoutTemplate>
          <table runat="server" id="tblEmployees" 
                 cellspacing="0" cellpadding="1" width="440px" border="1">
            <tr id="itemPlaceholder" runat="server"></tr>
          </table>
          <asp:DataPager ID="EmployeesDataPager" runat="server" PageSize="10">
            <Fields>
              <asp:NumericPagerField />
            </Fields>
          </asp:DataPager>
        </LayoutTemplate>
        <ItemTemplate>
          <tr runat="server">
            <td>
              <asp:Label runat="server" ID="NameLabel" 
                Text='<%#Eval("LastName") + ", " + Eval("FirstName") %>' />
            </td>
            <td style="width:80px">
              <asp:LinkButton runat="server" 
                ID="SelectEmployeeButton" 
                Text="Add To List" 
                CommandName="AddToList" 
                CommandArgument='<%#Eval("LastName") + ", " + Eval("FirstName") %>' />
            </td>
          </tr>
        </ItemTemplate>
      </asp:ListView>
      
      <br /><br />
      <b>Selected Employees:</b><br />
      <asp:ListBox runat="server" ID="SelectedEmployeesListBox" Rows="10" Width="300px" />
       
      <!-- 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="EmployeesDataSource" runat="server" 
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        SelectCommand="SELECT [EmployeeID], [FirstName], [LastName]
                       FROM HumanResources.vEmployee
                       ORDER BY [LastName], [FirstName], [EmployeeID]">
      </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">
  Protected Sub EmployeesListView_OnItemCommand(ByVal sender As Object, _
  ByVal e As ListViewCommandEventArgs)
    
    If String.Equals(e.CommandName, "AddToList") Then
      
      ' Verify that the employee ID is not already in the list. If not, add the
      ' employee to the list.
      Dim dataItem As ListViewDataItem = CType(e.Item, ListViewDataItem)
      Dim employeeID As String = _
        EmployeesListView.DataKeys(dataItem.DisplayIndex).Value.ToString()
      
      If SelectedEmployeesListBox.Items.FindByValue(employeeID) Is Nothing Then
        Dim item As ListItem = _
          New ListItem(e.CommandArgument.ToString(), employeeID)
        SelectedEmployeesListBox.Items.Add(item)
      End If
      
    End If
    
  End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head2" runat="server">
    <title>Employee List</title>
  </head>
  <body>
    <form id="form1" runat="server">
      <asp:ListView runat="server" 
        ID="EmployeesListView"
        OnItemCommand="EmployeesListView_OnItemCommand"
        DataSourceID="EmployeesDataSource" 
        DataKeyNames="EmployeeID">
        <LayoutTemplate>
          <table runat="server" id="tblEmployees" 
                 cellspacing="0" cellpadding="1" width="440px" border="1">
            <tr id="itemPlaceholder" runat="server"></tr>
          </table>
          <asp:DataPager ID="EmployeesDataPager" runat="server" PageSize="10">
            <Fields>
              <asp:NumericPagerField />
            </Fields>
          </asp:DataPager>
        </LayoutTemplate>
        <ItemTemplate>
          <tr runat="server">
            <td>
              <asp:Label runat="server" ID="NameLabel" 
                Text='<%#Eval("LastName") & ", " & Eval("FirstName") %>' />
            </td>
            <td style="width:80px">
              <asp:LinkButton runat="server" 
                ID="SelectEmployeeButton" 
                Text="Add To List" 
                CommandName="AddToList" 
                CommandArgument='<%#Eval("LastName") & ", " & Eval("FirstName") %>' />
            </td>
          </tr>
        </ItemTemplate>
      </asp:ListView>
      
      <br /><br />
      <b>Selected Employees:</b><br />
      <asp:ListBox runat="server" ID="SelectedEmployeesListBox" Rows="10" Width="300px" />
       
      <!-- 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="EmployeesDataSource" runat="server" 
        ConnectionString="<%$ ConnectionStrings:AdventureWorks_DataConnectionString %>"
        SelectCommand="SELECT [EmployeeID], [FirstName], [LastName]
                       FROM HumanResources.vEmployee
                       ORDER BY [LastName], [FirstName], [EmployeeID]">
      </asp:SqlDataSource>
    </form>
  </body>
</html>

Commenti

L'evento ItemCommand viene generato quando si fa clic su un pulsante nel controllo ListView.The ItemCommand event is raised when a button in the ListView control is clicked. In questo modo è possibile fornire un metodo di gestione degli eventi che esegua una routine personalizzata ogni volta che si verifica questo evento.This enables you to provide an event-handling method that performs a custom routine whenever this event occurs.

Nota

Il controllo ListView genera anche altri eventi quando si fa clic su determinati pulsanti (ad esempio, i pulsanti con la proprietà CommandName impostata su "Delete", "Update" o "Page").The ListView control also raises other events when certain buttons are clicked (for example, buttons with the CommandName property set to "Delete", "Update", or "Page"). Quando si utilizza uno di questi pulsanti, è possibile gestire uno degli eventi specializzati forniti dal controllo, ad esempio gli eventi ItemDeleted o ItemDeleting.When you use one of these buttons, you can handle one of the specialized events that are provided by the control, such as the ItemDeleted or ItemDeleting events.

Un oggetto ListViewCommandEventArgs viene passato al metodo di gestione degli eventi, che consente di determinare il nome del comando e l'argomento del comando del pulsante su cui è stato fatto clic.A ListViewCommandEventArgs object is passed to the event-handling method, which enables you to determine the command name and command argument of the button that was clicked. Per determinare il nome del comando, utilizzare la proprietà CommandName e per determinare l'argomento del comando utilizzare la proprietà CommandArgument.To determine the command name use the CommandName property, and to determine the command argument, use the CommandArgument property. È anche possibile accedere al controllo Button che ha generato l'evento usando la proprietà CommandSource.You can also access the button control that raised the event by using the CommandSource property.

Per un elenco dei valori iniziali delle proprietà di un'istanza della classe ListViewCommandEventArgs, vedere il costruttore ListViewCommandEventArgs.For a list of initial property values for an instance of the ListViewCommandEventArgs class, see the ListViewCommandEventArgs constructor.

Costruttori

ListViewCommandEventArgs(ListViewItem, Object, CommandEventArgs)

Inizializza una nuova istanza della classe ListViewCommandEventArgs utilizzando l'origine del comando e gli argomenti dell'evento specificati.Initializes a new instance of the ListViewCommandEventArgs class by using the specified source of the command and event arguments.

Proprietà

CommandArgument

Ottiene l'argomento del comando.Gets the argument for the command.

(Ereditato da CommandEventArgs)
CommandName

Ottiene il nome del comando.Gets the name of the command.

(Ereditato da CommandEventArgs)
CommandSource

Ottiene l'origine del comando.Gets the source of the command.

Handled

Ottiene o imposta un valore che indica se il controllo ha gestito l'evento.Gets or sets a value that indicates whether the control has handled the event.

Item

Ottiene l'elemento dei dati per il quale è stato emesso il comando.Gets the data item for which the command was issued.

Metodi

Equals(Object)

Determina se l'oggetto specificato è uguale all'oggetto corrente.Determines whether the specified object is equal to the current object.

(Ereditato da Object)
GetHashCode()

Funge da funzione hash predefinita.Serves as the default hash function.

(Ereditato da Object)
GetType()

Ottiene l'oggetto Type dell'istanza corrente.Gets the Type of the current instance.

(Ereditato da Object)
MemberwiseClone()

Crea una copia superficiale dell'oggetto Object corrente.Creates a shallow copy of the current Object.

(Ereditato da Object)
ToString()

Restituisce una stringa che rappresenta l'oggetto corrente.Returns a string that represents the current object.

(Ereditato da Object)

Si applica a

Vedi anche