Calendar.OnSelectionChanged Método
Definição
Importante
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Aumenta o SelectionChanged evento do Calendar controlo e permite-te fornecer um handler personalizado para o SelectionChanged evento.
protected:
virtual void OnSelectionChanged();protected virtual void OnSelectionChanged();abstract member OnSelectionChanged : unit -> unit
override this.OnSelectionChanged : unit -> unitProtected Overridable Sub OnSelectionChanged ()Exemplos
O exemplo de código seguinte demonstra como especificar e programar um handler para o SelectionChanged evento para mostrar o número de itens selecionados no Calendar controlo.
<%@ Page Language="C#" AutoEventWireup="True" %>
<!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>Calendar SelectionChanged Example</title>
<script runat="server">
void Selection_Change(Object sender, EventArgs e)
{
// Clear the current text.
Message.Text = "";
// Iterate through the SelectedDates collection and display the
// dates selected in the Calendar control.
foreach(DateTime day in Calendar1.SelectedDates)
{
Message.Text += day.Date.ToShortDateString() + "<br />";
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Calendar SelectionChanged Example</h3>
Select dates on the Calendar control.<br /><br />
<asp:Calendar ID="Calendar1" runat="server"
SelectionMode="DayWeekMonth"
ShowGridLines="True"
OnSelectionChanged="Selection_Change">
<SelectedDayStyle BackColor="Yellow"
ForeColor="Red">
</SelectedDayStyle>
</asp:Calendar>
<hr />
<table border="1">
<tr style="background-color:silver">
<th>
Selected Dates:
</th>
</tr>
<tr>
<td>
<asp:Label id="Message"
Text="No dates selected."
runat="server"/>
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!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>Calendar SelectionChanged Example</title>
<script runat="server">
Sub Selection_Change(sender As Object, e As EventArgs)
' Clear the current text.
Message.Text = ""
' Iterate through the SelectedDates collection and display the
' dates selected in the Calendar control.
Dim day As DateTime
For Each day In Calendar1.SelectedDates
Message.Text &= day.Date.ToShortDateString() & "<br />"
Next
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Calendar SelectionChanged Example</h3>
Select dates on the Calendar control.<br /><br />
<asp:Calendar ID="Calendar1" runat="server"
SelectionMode="DayWeekMonth"
ShowGridLines="True"
OnSelectionChanged="Selection_Change">
<SelectedDayStyle BackColor="Yellow"
ForeColor="Red">
</SelectedDayStyle>
</asp:Calendar>
<hr />
<table border="1">
<tr style="background-color:silver">
<th>
Selected Dates:
</th>
</tr>
<tr>
<td>
<asp:Label id="Message"
Text="No dates selected."
runat="server"/>
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>
<!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>Calendar SelectionChanged Example</title>
<script runat="server">
void Selection_Change(Object sender, EventArgs e)
{
// Clear the current text.
Message.Text = "";
// Iterate through the SelectedDates collection and display the
// dates selected in the Calendar control.
foreach(DateTime day in Calendar1.SelectedDates)
{
Message.Text += day.Date.ToShortDateString() + "<br />";
}
}
void Page_Load(Object sender, EventArgs e)
{
// Manually register the event-handling method for the
// SelectionChanged event of the Calendar control.
Calendar1.SelectionChanged += new EventHandler(this.Selection_Change);
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Calendar SelectionChanged Example</h3>
Select a day, week, or month on the Calendar control.<br /><br />
<asp:Calendar ID="Calendar1" runat="server"
SelectionMode="DayWeekMonth"
ShowGridLines="True">
<SelectedDayStyle BackColor="Yellow"
ForeColor="Red">
</SelectedDayStyle>
</asp:Calendar>
<hr />
<table border="1">
<tr style="background-color:silver">
<th>
Selected dates
</th>
</tr>
<tr>
<td>
<asp:Label id="Message"
Text="No dates selected."
runat="server"/>
</td>
</tr>
</table>
</form>
</body>
</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!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>Calendar SelectionChanged Example</title>
<script runat="server">
Sub Selection_Change(sender As Object, e As EventArgs)
' Clear the current text.
Message.Text = ""
' Iterate through the SelectedDates collection and display the
' dates selected in the Calendar control.
Dim day As DateTime
For Each day In Calendar1.SelectedDates
Message.Text &= day.Date.ToShortDateString() & "<br />"
Next
End Sub
Sub Page_Load(sender As Object, e As EventArgs)
' Manually register the event-handling method for the
' SelectionChanged event of the Calendar control.
AddHandler Calendar1.SelectionChanged, AddressOf Selection_Change
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3>Calendar SelectionChanged Example</h3>
Select a day, week, or month on the Calendar control.<br /><br />
<asp:Calendar ID="Calendar1" runat="server"
SelectionMode="DayWeekMonth"
ShowGridLines="True">
<SelectedDayStyle BackColor="Yellow"
ForeColor="Red">
</SelectedDayStyle>
</asp:Calendar>
<hr />
<table border="1">
<tr style="background-color:silver">
<th>
Selected Dates:
</th>
</tr>
<tr>
<td>
<asp:Label id="Message"
Text="No dates selected."
runat="server"/>
</td>
</tr>
</table>
</form>
</body>
</html>
Observações
O SelectionChanged evento é ativado quando o utilizador seleciona um dia, uma semana ou um mês inteiro clicando nos controlos do seletor de datas.
Levantar um evento invoca o gestor de eventos através de um delegado. Para mais informações, consulte Manuseio e Levantamento de Eventos.
O OnSelectionChanged método também permite que classes derivadas tratem do evento sem anexar um delegado. Esta é a técnica preferida para lidar com o evento numa classe derivada.
Notas para Herdeiros
Ao substituir OnSelectionChanged() uma classe derivada, certifique-se de chamar o método da OnSelectionChanged() classe base para que os delegados registados recebam o evento.