Sintassi dichiarativa per il controllo server Web View
Aggiornamento: novembre 2007
Rappresenta un controllo che funge da contenitore per un gruppo di controlli all'interno di un controllo MultiView.
<asp:View
EnableTheming="True|False"
EnableViewState="True|False"
ID="string"
OnActivate="Activate event handler"
OnDataBinding="DataBinding event handler"
OnDeactivate="Deactivate event handler"
OnDisposed="Disposed event handler"
OnInit="Init event handler"
OnLoad="Load event handler"
OnPreRender="PreRender event handler"
OnUnload="Unload event handler"
runat="server"
SkinID="string"
Visible="True|False"
/>
Note
Il controllo View è un contenitore per un gruppo di controlli. Un controllo View deve sempre essere contenuto in un controllo MultiView. È possibile definire un solo controllo View alla volta come visualizzazione attiva all'interno di un controllo MultiView.
Per ulteriori informazioni sull'utilizzo dei controlli View e MultiView, vedere Cenni preliminari sui controlli server Web MultiView e View.
Esempio
Nell'esempio di codice riportato di seguito viene illustrato come utilizzare un controllo MultiView per creare un sondaggio di base. Ogni controllo View rappresenta una domanda distinta del sondaggio. Quando l'utente fa clic sul pulsante Previous in una pagina, la proprietà ActiveViewIndex viene decrementata per passare al controllo View precedente. Quando l'utente fa clic sul pulsante Next in una pagina, la proprietà ActiveViewIndex viene incrementata per passare al controllo View successivo.
<%@ 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" >
<head>
<title>MultiView ActiveViewIndex Example</title>
<script runat="server">
Sub NextButton_Command(sender As Object, e As System.EventArgs)
' Determine which button was clicked
' and set the ActiveViewIndex property to
' the view selected by the user.
If (DevPollMultiView.ActiveViewIndex > -1) AND DevPollMultiView.ActiveViewIndex < 3 Then
' Increment the ActiveViewIndex property
' by one to advance to the next view.
DevPollMultiView.ActiveViewIndex += 1
ElseIf DevPollMultiView.ActiveViewIndex = 3 Then
' This is the final view.
' The user wants to save the survey results.
' Insert code here to save survey results.
' Disable the navigation buttons.
Page4Save.Enabled = False
Page4Restart.Enabled = False
Else
Throw New Exception("An error occurred.")
End If
End Sub
Sub BackButton_Command(ByVal sender As Object, ByVal e As System.EventArgs)
If (DevPollMultiView.ActiveViewIndex > 0) And DevPollMultiView.ActiveViewIndex <= 2 Then
' Decrement the ActiveViewIndex property
' by one to return to the previous view.
DevPollMultiView.ActiveViewIndex -= 1
ElseIf DevPollMultiView.ActiveViewIndex = 3 Then
' This is the final view.
' The user wants to restart the survey.
' Return to the first view.
DevPollMultiView.ActiveViewIndex = 0
Else
Throw New Exception("An error occurred.")
End If
End Sub
</script>
</head>
<body>
<form id="Form1" runat="Server">
<h3>MultiView ActiveViewIndex Example</h3>
<asp:Panel id="Page1ViewPanel"
Width="330px"
Height="150px"
HorizontalAlign ="Left"
Font-size="12"
BackColor="#C0C0FF"
BorderColor="#404040"
BorderStyle="Double"
runat="Server">
<asp:MultiView id="DevPollMultiView"
ActiveViewIndex="0"
runat="Server">
<asp:View id="Page1"
runat="Server">
<asp:Label id="Page1Label"
Font-bold="true"
Text="What kind of applications do you develop?"
runat="Server"
AssociatedControlID="Page1">
</asp:Label><br /><br />
<asp:RadioButton id="Page1Radio1"
Text="Web Applications"
Checked="False"
GroupName="RadioGroup1"
runat="server" >
</asp:RadioButton><br />
<asp:RadioButton id="Page1Radio2"
Text="Windows Forms Applications"
Checked="False"
GroupName="RadioGroup1"
runat="server" >
</asp:RadioButton><br /><br /><br />
<asp:Button id="Page1Next"
Text = "Next"
OnClick="NextButton_Command"
Height="25"
Width="70"
runat= "Server">
</asp:Button>
</asp:View>
<asp:View id="Page2"
runat="Server">
<asp:Label id="Page2Label"
Font-bold="true"
Text="How long have you been a developer?"
runat="Server"
AssociatedControlID="Page2">
</asp:Label><br /><br />
<asp:RadioButton id="Page2Radio1"
Text="Less than five years"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br />
<asp:RadioButton id="Page2Radio2"
Text="More than five years"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br /><br /><br />
<asp:Button id="Page2Back"
Text = "Previous"
OnClick="BackButton_Command"
Height="25"
Width="70"
runat= "Server">
</asp:Button>
<asp:Button id="Page2Next"
Text = "Next"
OnClick="NextButton_Command"
Height="25"
Width="70"
runat="Server">
</asp:Button>
</asp:View>
<asp:View id="Page3"
runat="Server">
<asp:Label id="Page3Label1"
Font-bold="true"
Text= "What is your primary programming language?"
runat="Server"
AssociatedControlID="Page3">
</asp:Label><br /><br />
<asp:RadioButton id="Page3Radio1"
Text="Visual Basic .NET"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br />
<asp:RadioButton id="Page3Radio2"
Text="C#"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br />
<asp:RadioButton id="Page3Radio3"
Text="C++"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br /><br />
<asp:Button id="Page3Back"
Text = "Previous"
OnClick="BackButton_Command"
Height="25"
Width="70"
runat="Server">
</asp:Button>
<asp:Button id="Page3Next"
Text = "Next"
OnClick="NextButton_Command"
Height="25"
Width="70"
runat="Server">
</asp:Button><br />
</asp:View>
<asp:View id="Page4"
runat="Server">
<asp:Label id="Label1"
Font-bold="true"
Text = "Thank you for taking the survey."
runat="Server"
AssociatedControlID="Page4">
</asp:Label>
<br /><br /><br /><br /><br /><br />
<asp:Button id="Page4Save"
Text = "Save Responses"
OnClick="NextButton_Command"
Height="25"
Width="110"
runat="Server">
</asp:Button>
<asp:Button id="Page4Restart"
Text = "Retake Survey"
OnClick="BackButton_Command"
Height="25"
Width="110"
runat= "Server">
</asp:Button>
</asp:View>
</asp:MultiView>
</asp:Panel>
</form>
</body>
</html>
<%@ 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" >
<head>
<title>MultiView ActiveViewIndex Example</title>
<script runat="server">
protected void NextButton_Command(object sender, EventArgs e)
{
// Determine which button was clicked
// and set the ActiveViewIndex property to
// the view selected by the user.
if (DevPollMultiView.ActiveViewIndex > -1 & DevPollMultiView.ActiveViewIndex < 3)
{
// Increment the ActiveViewIndex property
// by one to advance to the next view.
DevPollMultiView.ActiveViewIndex += 1;
}
else if (DevPollMultiView.ActiveViewIndex == 3)
{
// This is the final view.
// The user wants to save the survey results.
// Insert code here to save survey results.
// Disable the navigation buttons.
Page4Save.Enabled = false;
Page4Restart.Enabled = false;
}
else
{
throw new Exception("An error occurred.");
}
}
protected void BackButton_Command(object sender, EventArgs e)
{
if (DevPollMultiView.ActiveViewIndex > 0 & DevPollMultiView.ActiveViewIndex <= 2)
{
// Decrement the ActiveViewIndex property
// by one to return to the previous view.
DevPollMultiView.ActiveViewIndex -= 1;
}
else if (DevPollMultiView.ActiveViewIndex == 3)
{
// This is the final view.
// The user wants to restart the survey.
// Return to the first view.
DevPollMultiView.ActiveViewIndex = 0;
}
else
{
throw new Exception("An error occurred.");
}
}
</script>
</head>
<body>
<form id="Form1" runat="Server">
<h3>MultiView ActiveViewIndex Example</h3>
<asp:Panel id="Page1ViewPanel"
Width="330px"
Height="150px"
HorizontalAlign="Left"
Font-size="12"
BackColor="#C0C0FF"
BorderColor="#404040"
BorderStyle="Double"
runat="Server">
<asp:MultiView id="DevPollMultiView"
ActiveViewIndex="0"
runat="Server">
<asp:View id="Page1"
runat="Server">
<asp:Label id="Page1Label"
Font-bold="true"
Text="What kind of applications do you develop?"
runat="Server"
AssociatedControlID="Page1">
</asp:Label><br /><br />
<asp:RadioButton id="Page1Radio1"
Text="Web Applications"
Checked="False"
GroupName="RadioGroup1"
runat="server" >
</asp:RadioButton><br />
<asp:RadioButton id="Page1Radio2"
Text="Windows Forms Applications"
Checked="False"
GroupName="RadioGroup1"
runat="server" >
</asp:RadioButton><br /><br /><br />
<asp:Button id="Page1Next"
Text = "Next"
OnClick="NextButton_Command"
Height="25"
Width="70"
runat= "Server">
</asp:Button>
</asp:View>
<asp:View id="Page2"
runat="Server">
<asp:Label id="Page2Label"
Font-bold="true"
Text="How long have you been a developer?"
runat="Server"
AssociatedControlID="Page2">
</asp:Label><br /><br />
<asp:RadioButton id="Page2Radio1"
Text="Less than five years"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br />
<asp:RadioButton id="Page2Radio2"
Text="More than five years"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br /><br /><br />
<asp:Button id="Page2Back"
Text = "Previous"
OnClick="BackButton_Command"
Height="25"
Width="70"
runat= "Server">
</asp:Button>
<asp:Button id="Page2Next"
Text = "Next"
OnClick="NextButton_Command"
Height="25"
Width="70"
runat="Server">
</asp:Button>
</asp:View>
<asp:View id="Page3"
runat="Server">
<asp:Label id="Page3Label1"
Font-bold="true"
Text= "What is your primary programming language?"
runat="Server"
AssociatedControlID="Page3">
</asp:Label><br /><br />
<asp:RadioButton id="Page3Radio1"
Text="Visual Basic .NET"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br />
<asp:RadioButton id="Page3Radio2"
Text="C#"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br />
<asp:RadioButton id="Page3Radio3"
Text="C++"
Checked="False"
GroupName="RadioGroup1"
runat="Server">
</asp:RadioButton><br /><br />
<asp:Button id="Page3Back"
Text = "Previous"
OnClick="BackButton_Command"
Height="25"
Width="70"
runat="Server">
</asp:Button>
<asp:Button id="Page3Next"
Text = "Next"
OnClick="NextButton_Command"
Height="25"
Width="70"
runat="Server">
</asp:Button><br />
</asp:View>
<asp:View id="Page4"
runat="Server">
<asp:Label id="Label1"
Font-bold="true"
Text = "Thank you for taking the survey."
runat="Server"
AssociatedControlID="Page4">
</asp:Label>
<br /><br /><br /><br /><br /><br />
<asp:Button id="Page4Save"
Text = "Save Responses"
OnClick="NextButton_Command"
Height="25"
Width="110"
runat="Server">
</asp:Button>
<asp:Button id="Page4Restart"
Text = "Retake Survey"
OnClick="BackButton_Command"
Height="25"
Width="110"
runat= "Server">
</asp:Button>
</asp:View>
</asp:MultiView>
</asp:Panel>
</form>
</body>
</html>
Vedere anche
Concetti
Cenni preliminari sui controlli server Web MultiView e View