Calendar.OnSelectionChanged 方法
定義
重要
部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。
引發 SelectionChanged 控制項的 Calendar 事件，並允許您提供 SelectionChanged 事件的自訂處理常式。
protected:
virtual void OnSelectionChanged();protected virtual void OnSelectionChanged ();abstract member OnSelectionChanged : unit -> unit
override this.OnSelectionChanged : unit -> unitProtected Overridable Sub OnSelectionChanged ()範例
下列程式碼範例示範如何指定和撰寫事件處理常式 SelectionChanged 的程式碼，以顯示控制項中 Calendar 選取的專案數。
<%@ 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>
備註
SelectionChanged當使用者按一下日期選擇器控制項來選取一天、一周或整個月時，就會引發事件。
引發事件會透過委派叫用此事件處理常式。 如需詳細資訊，請參閱 處理和引發事件。
OnSelectionChanged 方法也允許衍生類別處理事件，而不用附加委派。 這是在衍生類別中處理事件的慣用技巧。
給繼承者的注意事項
當在衍生類別中覆寫 OnSelectionChanged() 時，請確定呼叫基底類別的 OnSelectionChanged() 方法，使已註冊的委派能接收到事件。
