CheckBox 构造函数
定义
重要
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初始化 CheckBox 类的新实例。
public:
CheckBox();public CheckBox ();Public Sub New ()示例
注意
下面的代码示例使用单文件代码模型，如果直接复制到代码隐藏文件中，可能无法正常工作。 必须将此代码示例复制到扩展名为 .aspx 的空文本文件中。 有关 Web 窗体代码模型的详细信息，请参阅 ASP.NET Web 窗体页代码模型。
<%@ 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> CheckBox Constructor Example </title>
<script runat="server">
void Page_Load(Object sender, EventArgs e)
{
// Create new CheckBox control.
CheckBox NewCheckBox = new CheckBox();
NewCheckBox.ID="FeatureCheckBox";
NewCheckBox.Text="Enable feature";
NewCheckBox.AutoPostBack = true;
// Register the event-handling method for the CheckedChanged event.
NewCheckBox.CheckedChanged += new EventHandler(this.Check_Change);
// Add the control to the Controls collection of the
// PlaceHolder control.
Place.Controls.Clear();
Place.Controls.Add(NewCheckBox);
}
void Check_Change(Object sender, EventArgs e)
{
// Retrieve the CheckBox control from the PlaceHolder control.
CheckBox check = (CheckBox)Place.FindControl("FeatureCheckBox");
// Display the appropriate message based on the state of the
// CheckBox control.
if(check.Checked)
{
Message.Text = "Feature enabled.";
}
else
{
Message.Text = "Feature disabled.";
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<h3> CheckBox Constructor Example </h3>
Click the check box.
<br /><br />
<asp:Placeholder id="Place"
runat="server"/>
<br /><br />
<asp:Label id="Message"
runat="server"/>
</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> CheckBox Constructor Example </title>
<script runat="server">
Sub Page_Load(sender As Object, e As EventArgs)
' Create new CheckBox control.
Dim NewCheckBox As CheckBox = New CheckBox()
NewCheckBox.ID="FeatureCheckBox"
NewCheckBox.Text="Enable feature"
NewCheckBox.AutoPostBack = True
' Register the event handling method for the CheckedChanged event.
AddHandler NewCheckBox.CheckedChanged, AddressOf Check_Change
' Add the control to the Controls collection of the
' PlaceHolder control.
Place.Controls.Clear()
Place.Controls.Add(NewCheckBox)
End Sub
Sub Check_Change(sender As Object, e As EventArgs)
' Retrieve the CheckBox control from the PlaceHolder control.
Dim check As CheckBox = _
CType(Place.FindControl("FeatureCheckBox"), CheckBox)
' Display the appropriate message based on the state of the
' CheckBox control.
If check.Checked Then
Message.Text = "Feature enabled."
Else
Message.Text = "Feature disabled."
End If
End Sub
</script>
</head>
<body>
<form id="form1" runat="server">
<h3> CheckBox Constructor Example </h3>
Click the check box.
<br /><br />
<asp:Placeholder id="Place"
runat="server"/>
<br /><br />
<asp:Label id="Message"
runat="server"/>
</form>
</body>
</html>
注解
使用此构造函数创建和初始化 类的新实例 CheckBox 。
