MultiView.OnActiveViewChanged(EventArgs) Metodo

Definizione

Genera l'evento ActiveViewChanged di un controllo MultiView,

protected:
 virtual void OnActiveViewChanged(EventArgs ^ e);
protected virtual void OnActiveViewChanged (EventArgs e);
abstract member OnActiveViewChanged : EventArgs -> unit
override this.OnActiveViewChanged : EventArgs -> unit
Protected Overridable Sub OnActiveViewChanged (e As EventArgs)

Parametri

e
EventArgs

Oggetto EventArgs che contiene i dati dell'evento.

Esempio

Nell'esempio seguente viene illustrato come specificare e codice un gestore eventi per l'evento ActiveViewChanged di un MultiView controllo. Quando la visualizzazione attiva viene modificata, viene visualizzato un messaggio in un Label controllo nella pagina.

Nota

L'esempio di codice seguente usa il modello di codice a file singolo e potrebbe non funzionare correttamente se copiato direttamente in un file code-behind. Questo esempio di codice deve essere copiato in un file di testo vuoto con un'estensione .aspx. Per altre informazioni sul modello di codice Web Forms, vedere ASP.NET modello di codice della pagina Web Forms.

<%@ 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 MultiView1_ActiveViewChanged(object sender, EventArgs e)
    {
        String activeView;
        activeView = MultiView1.GetActiveView().ID;
        ActiveViewLabel.Text = "The ActiveViewChanged event was raised." +
                               "<br/>" + "The active view is set to " + activeView;
    }

    protected void LinkButton_Command(object sender, CommandEventArgs e)
    {
        // Determine which link button was clicked
        // and set the active view to
        // the view selected by the user.
        switch (e.CommandArgument.ToString())
        {
            case "DefaultView":
                MultiView1.SetActiveView(DefaultView);
                break;
            case "News":
                MultiView1.SetActiveView(NewsView);
                break;
            case "Shopping":
                MultiView1.SetActiveView(ShoppingView);
                break;
        }
        
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h3>MultiView.ActiveViewChangedEvent Example</h3>

         <asp:MultiView id="MultiView1"
            ActiveViewIndex="0"
            OnActiveViewChanged="MultiView1_ActiveViewChanged"
            runat="Server">

            <asp:View id="DefaultView" 
                runat="Server">                

                <asp:Panel id="DefaultViewPanel" 
                    Width="330px" 
                    BackColor="#C0C0FF" 
                    BorderColor="#404040"
                    BorderStyle="Double"
                    runat="Server">  

                    <asp:Label id="DefaultLabel1" 
                        Font-bold="true"
                        Font-size="14" 
                        Text="The Default View"
                        runat="Server"
                        AssociatedControlID="DefaultView">
                    </asp:Label>                  

                    <asp:BulletedList id="DefaultBulletedList1" 
                        BulletStyle="Disc" 
                        DisplayMode="Hyperlink"
                        Target="_blank"
                        runat="Server">
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's Weather</asp:ListItem>
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's Stock Quotes</asp:ListItem>
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's News Headlines</asp:ListItem>
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's Featured Shopping</asp:ListItem>
                    </asp:BulletedList>

                    <hr />

                    <asp:Label id="DefaultLabel2"                      
                        Font-size="12" 
                        Text="Click a link to display a different view:"
                        runat="Server">
                    </asp:Label><br />
                
                    <asp:LinkButton id="Default_NewsLink" 
                        Text="Go to News View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="News" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton>

                    <asp:LinkButton id="Default_ShoppingLink"
                        Text="Go to Shopping View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="Shopping" 
                        CommandName="Link"
                        Width="150px"
                        runat="server">
                    </asp:LinkButton><br /><br />

                </asp:Panel>

            </asp:View>

            <asp:View id="NewsView" 
                runat="Server">

                <asp:Panel id="NewsPanel1" 
                    Width="330px" 
                    BackColor="#C0FFC0" 
                    BorderColor="#404040"
                    BorderStyle="Double"
                    runat="Server">

                    <asp:Label id="NewsLabel1" 
                        Font-bold="true"
                        Font-size="14"
                        Text="The News View"
                        runat="Server"
                        AssociatedControlID="NewsView">                    
                    </asp:Label>

                    <asp:BulletedList id="NewsBulletedlist1" 
                        BulletStyle="Disc" 
                        DisplayMode="Hyperlink"
                        Target="_blank"
                        runat="Server">
                            <asp:ListItem Value="http://www.microsoft.com">Today's International Headlines</asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Today's National Headlines</asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Today's Local News</asp:ListItem>
                    </asp:BulletedList>
                    
                    <hr />

                    <asp:Label id="NewsLabel2"                      
                        Font-size="12" 
                        Text="Click a link to display a different view:"
                        runat="Server">
                    </asp:Label><br />

                    <asp:LinkButton id="News_DefaultLink" 
                        Text="Go to the Default View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="DefaultView" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton>

                    <asp:LinkButton id="News_ShoppingLink" 
                        Text="Go to Shopping View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="Shopping" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton><br /><br />

                </asp:Panel>

            </asp:View>

            <asp:View id="ShoppingView" 
                runat="Server">

                <asp:Panel id="ShoppingPanel1" 
                    Width="330px" 
                    BackColor="#FFFFC0" 
                    BorderColor="#404040"
                    BorderStyle="Double"
                    runat="Server">

                    <asp:Label id="ShoppingLabel1" 
                        Font-Bold="true"
                        Font-size="14"                         
                        Text="The Shopping View"
                        runat="Server"
                        AssociatedControlID="ShoppingView">
                    </asp:Label>

                    <asp:BulletedList id="ShoppingBulletedlist1" 
                        BulletStyle="Disc" 
                        DisplayMode="Hyperlink"
                        Target="_blank"
                        runat="Server">
                            <asp:ListItem Value="http://www.microsoft.com">Shop for Home and Garden </asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Shop for Women's Fashions</asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Shop for Men's Fashions</asp:ListItem>
                    </asp:BulletedList>
                    
                    <hr />

                    <asp:Label id="ShoppingLabel2" 
                        Font-size="12" 
                        Text="Click a link to display a different view:"
                        runat="Server">
                    </asp:Label><br />

                    <asp:LinkButton id="Shopping_DefaultLink" 
                        Text="Go to the Default View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="DefaultView" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton>

                    <asp:LinkButton id="Shopping_NewsLink"
                        Text="Go to News View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="News" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton><br /><br />

                </asp:Panel>

            </asp:View>

        </asp:MultiView>
        
        <hr />
        
        <asp:Label id="ActiveViewLabel"             
            BorderStyle="None"
            Font-Size="Small"
            BackColor="#ffff66"
            runat="Server" > 
        </asp:Label>
    
    </div>
    </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 MultiView1_ActiveViewChanged(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim activeView As String
        activeView = MultiView1.GetActiveView().ID
        ActiveViewLabel.Text = "The ActiveViewChanged event was raised." + _
                               "<br/>" + "The active view is set to " + activeView
                                   
    End Sub

    Sub LinkButton_Command(ByVal sender As Object, ByVal e As CommandEventArgs)
        ' Determine which link button was clicked
        ' and set the active view to
        ' the view selected by the user.
        Select Case (e.CommandArgument.ToString())
            Case "DefaultView"
                MultiView1.SetActiveView(DefaultView)
            Case "News"
                MultiView1.SetActiveView(NewsView)
            Case "Shopping"
                MultiView1.SetActiveView(ShoppingView)
        End Select

    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <h3>MultiView.ActiveViewChangedEvent Example</h3>

         <asp:MultiView id="MultiView1"
            ActiveViewIndex="0"
            OnActiveViewChanged="MultiView1_ActiveViewChanged"
            runat="Server">

            <asp:View id="DefaultView" 
                runat="Server">                

                <asp:Panel id="DefaultViewPanel" 
                    Width="330px" 
                    BackColor="#C0C0FF" 
                    BorderColor="#404040"
                    BorderStyle="Double"
                    runat="Server">  

                    <asp:Label id="DefaultLabel1" 
                        Font-bold="true"
                        Font-size="14" 
                        Text="The Default View"
                        runat="Server"
                        AssociatedControlID="DefaultView">
                    </asp:Label>                  

                    <asp:BulletedList id="DefaultBulletedList1" 
                        BulletStyle="Disc" 
                        DisplayMode="Hyperlink"
                        Target="_blank"
                        runat="Server">
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's Weather</asp:ListItem>
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's Stock Quotes</asp:ListItem>
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's News Headlines</asp:ListItem>
                            <asp:ListItem 
                                Value="http://www.microsoft.com">Today's Featured Shopping</asp:ListItem>
                    </asp:BulletedList>

                    <hr />

                    <asp:Label id="DefaultLabel2"                      
                        Font-size="12" 
                        Text="Click a link to display a different view:"
                        runat="Server">
                    </asp:Label><br />
                
                    <asp:LinkButton id="Default_NewsLink" 
                        Text="Go to News View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="News" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton>

                    <asp:LinkButton id="Default_ShoppingLink"
                        Text="Go to Shopping View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="Shopping" 
                        CommandName="Link"
                        Width="150px"
                        runat="server">
                    </asp:LinkButton><br /><br />

                </asp:Panel>

            </asp:View>

            <asp:View id="NewsView" 
                runat="Server">

                <asp:Panel id="NewsPanel1" 
                    Width="330px" 
                    BackColor="#C0FFC0" 
                    BorderColor="#404040"
                    BorderStyle="Double"
                    runat="Server">

                    <asp:Label id="NewsLabel1" 
                        Font-bold="true"
                        Font-size="14"
                        Text="The News View"
                        runat="Server"
                        AssociatedControlID="NewsView">                    
                    </asp:Label>

                    <asp:BulletedList id="NewsBulletedlist1" 
                        BulletStyle="Disc" 
                        DisplayMode="Hyperlink"
                        Target="_blank"
                        runat="Server">
                            <asp:ListItem Value="http://www.microsoft.com">Today's International Headlines</asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Today's National Headlines</asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Today's Local News</asp:ListItem>
                    </asp:BulletedList>
                    
                    <hr />

                    <asp:Label id="NewsLabel2"                      
                        Font-size="12" 
                        Text="Click a link to display a different view:"
                        runat="Server">
                    </asp:Label><br />

                    <asp:LinkButton id="News_DefaultLink" 
                        Text="Go to the Default View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="DefaultView" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton>

                    <asp:LinkButton id="News_ShoppingLink" 
                        Text="Go to Shopping View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="Shopping" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton><br /><br />

                </asp:Panel>

            </asp:View>

            <asp:View id="ShoppingView" 
                runat="Server">

                <asp:Panel id="ShoppingPanel1" 
                    Width="330px" 
                    BackColor="#FFFFC0" 
                    BorderColor="#404040"
                    BorderStyle="Double"
                    runat="Server">

                    <asp:Label id="ShoppingLabel1" 
                        Font-Bold="true"
                        Font-size="14"                         
                        Text="The Shopping View"
                        runat="Server"
                        AssociatedControlID="ShoppingView">
                    </asp:Label>

                    <asp:BulletedList id="ShoppingBulletedlist1" 
                        BulletStyle="Disc" 
                        DisplayMode="Hyperlink"
                        Target="_blank"
                        runat="Server">
                            <asp:ListItem Value="http://www.microsoft.com">Shop for Home and Garden </asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Shop for Women's Fashions</asp:ListItem>
                            <asp:ListItem Value="http://www.microsoft.com">Shop for Men's Fashions</asp:ListItem>
                    </asp:BulletedList>
                    
                    <hr />

                    <asp:Label id="ShoppingLabel2" 
                        Font-size="12" 
                        Text="Click a link to display a different view:"
                        runat="Server">
                    </asp:Label><br />

                    <asp:LinkButton id="Shopping_DefaultLink" 
                        Text="Go to the Default View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="DefaultView" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton>

                    <asp:LinkButton id="Shopping_NewsLink"
                        Text="Go to News View" 
                        OnCommand="LinkButton_Command"
                        CommandArgument="News" 
                        CommandName="Link"
                        Width="150px"
                        runat="Server">
                    </asp:LinkButton><br /><br />

                </asp:Panel>

            </asp:View>

        </asp:MultiView>
        
        <hr />
        
        <asp:Label id="ActiveViewLabel"             
            BorderStyle="None"
            Font-Size="Small"
            BackColor="#ffff66"
            runat="Server" > 
        </asp:Label>
    </div>
    </form>
</body>
</html>

Commenti

L'evento ActiveViewChanged viene generato quando il controllo attivo View all'interno di un MultiView controllo cambia tra post nel server e è possibile fornire un gestore personalizzato per questo evento.

Quando viene generato un evento, il gestore dell'evento viene richiamato tramite un delegato. Per altre informazioni, vedere Procedura: Usare eventi in un'applicazione Web Form.

Il metodo OnActiveViewChanged consente inoltre alle classi derivate di gestire l'evento senza associare un delegato. È la tecnica consigliata per la gestione dell'evento in una classe derivata.

Note per gli eredi

Quando si esegue l'override di OnActiveViewChanged(EventArgs) in una classe derivata, verificare di chiamare il metodo OnActiveViewChanged(EventArgs) della classe di base in modo che i delegati registrati ricevano l'evento.

Si applica a

Vedi anche