Form.Activated 事件
当使用代码激活或用户激活窗体时发生。
**命名空间:**System.Windows.Forms
**程序集:**System.Windows.Forms（在 system.windows.forms.dll 中）
语法
声明
Public Event Activated As EventHandler
用法
Dim instance As Form
Dim handler As EventHandler
AddHandler instance.Activated, handler
public event EventHandler Activated
public:
event EventHandler^ Activated {
void add (EventHandler^ value);
void remove (EventHandler^ value);
}
/** @event */
public void add_Activated (EventHandler value)
/** @event */
public void remove_Activated (EventHandler value)
JScript 支持使用事件，但不支持进行新的声明。
备注
若要在运行时使用代码激活窗体，请调用 Activate 方法。可以使用此事件处理一些任务，如根据在窗体未激活时对窗体数据所做的更改来更新窗体的内容。
有关处理事件的更多信息，请参见 使用事件。
示例
下面的代码示例阐释了如何使用 SetDesktopLocation、Closed、Load、Activated 和 Activate 成员。若要运行此示例，请将以下代码粘贴到一个名为 Form1 的窗体中，该窗体含有一个名为 Button1 的 Button 和两个分别名为 Label1 和 Label2 的 Label 控件。
Shared x As Integer = 200
Shared y As Integer = 200
Private Sub Button1_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles Button1.Click
' Create a new Form1 and set its Visible property to true.
Dim form2 As New Form1
form2.Visible = True
' Set the new form's desktop location so it appears below and
' to the right of the current form.
form2.SetDesktopLocation(x, y)
x += 30
y += 30
' Keep the current form active by calling the Activate method.
Me.Activate()
Me.Button1.Enabled = False
End Sub
' Updates the label text to reflect the current values of x and y,
' which was were incremented in the Button1 control's click event.
Private Sub Form1_Activated(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles MyBase.Activated
Label1.Text = "x: " & x & " y: " & y
Label2.Text = "Number of forms currently open: " & count
End Sub
Shared count As Integer = 0
Private Sub Form1_Closed(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles MyBase.Closed
count -= 1
End Sub
Private Sub Form1_Load(ByVal sender As Object, _
ByVal e As System.EventArgs) Handles MyBase.Load
count += 1
End Sub
static int x = 200;
static int y = 200;
private void Button1_Click(System.Object sender,
System.EventArgs e)
{
// Create a new Form1 and set its Visible property to true.
Form1 form2 = new Form1();
form2.Visible = true;
// Set the new form's desktop location so it
// appears below and to the right of the current form.
form2.SetDesktopLocation(x, y);
x += 30;
y += 30;
// Keep the current form active by calling the Activate
// method.
this.Activate();
this.Button1.Enabled = false;
}
// Updates the label text to reflect the current values of x
// and y, which was were incremented in the Button1 control's
// click event.
private void Form1_Activated(object sender, System.EventArgs e)
{
Label1.Text = "x: "+x+" y: "+y;
Label2.Text = "Number of forms currently open: "+count;
}
static int count = 0;
private void Form1_Closed(object sender, System.EventArgs e)
{
count -= 1;
}
private void Form1_Load(object sender, System.EventArgs e)
{
count += 1;
}
static int x = 200;
static int y = 200;
void Button1_Click( System::Object^ sender, System::EventArgs^ e )
{
// Create a new Form1 and set its Visible property to true.
Form1^ form2 = gcnew Form1;
form2->Visible = true;
// Set the new form's desktop location so it
// appears below and to the right of the current form.
form2->SetDesktopLocation( x, y );
x += 30;
y += 30;
// Keep the current form active by calling the Activate
// method.
this->Activate();
this->Button1->Enabled = false;
}
// Updates the label text to reflect the current values of x
// and y, which was were incremented in the Button1 control's
// click event.
void Form1_Activated( Object^ sender, System::EventArgs^ e )
{
Label1->Text = String::Format( "x: {0} y: {1}", x, y );
Label2->Text = String::Format( "Number of forms currently open: {0}", count );
}
static int count = 0;
void Form1_Closed( Object^ sender, System::EventArgs^ e )
{
count -= 1;
}
void Form1_Load( Object^ sender, System::EventArgs^ e )
{
count += 1;
}
private static int x = 200;
private static int y = 200;
private void button1_Click(Object sender, System.EventArgs e)
{
// Create a new Form1 and set its Visible property to true.
Form1 form2 = new Form1();
form2.set_Visible(true);
// Set the new form's desktop location so it
// appears below and to the right of the current form.
form2.SetDesktopLocation(x, y);
x += 30;
y += 30;
// Keep the current form active by calling the Activate
// method.
this.Activate();
this.button1.set_Enabled(false);
} //button1_Click
// Updates the label text to reflect the current values of x
// and y, which was were incremented in the button1 control's
// click event.
private void Form1_Activated(Object sender, System.EventArgs e)
{
label1.set_Text("x: " + x + " y: " + y);
label2.set_Text("Number of forms currently open: " + count);
} //Form1_Activated
private static int count = 0;
private void Form1_Closed(Object sender, System.EventArgs e)
{
count -= 1;
} //Form1_Closed
private void Form1_Load(Object sender, System.EventArgs e)
{
count += 1;
} //Form1_Load
平台
Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息
.NET Framework
受以下版本支持：2.0、1.1、1.0
.NET Compact Framework
受以下版本支持：2.0、1.0