Form.Activated Событие

Определение

Происходит при активизации формы, определенной в коде или заданной пользователем.Occurs when the form is activated in code or by the user.

public:
 event EventHandler ^ Activated;
public event EventHandler Activated;
member this.Activated : EventHandler 
Public Custom Event Activated As EventHandler 

Примеры

В следующем примере показано, как использовать члены SetDesktopLocation, Closed, Load, Activated и Activate.The following example demonstrates how to use the SetDesktopLocation, Closed, Load, Activated, and Activate members. Чтобы выполнить пример, вставьте следующий код в форму с именем Form1, которая содержит Button с именем Button1, и два элемента управления Label с именами Label1 и Label2.To run the example, paste the following code in a form called Form1 containing a Button called Button1 and two Label controls called Label1 and Label2.

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;
}
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;
}
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

Комментарии

Примечание

Если приложение активно и имеет несколько форм, активная форма является формой с фокусом ввода.When the application is active and has multiple forms, the active form is the form with the input focus. Невидимая форма не может быть активной формой.A form that is not visible cannot be the active form. Самый простой способ активировать видимую форму — щелкнуть ее или использовать соответствующую комбинацию клавиш.The simplest way to activate a visible form is to click it or use an appropriate keyboard combination.

Чтобы активировать форму во время выполнения с помощью кода, вызовите метод Activate.To activate a form at run time using code, call the Activate method. Это событие можно использовать для таких задач, как обновление содержимого формы на основе изменений, внесенных в данные формы, если форма не была активирована.You can use this event for tasks such as updating the contents of the form based on changes made to the form's data when the form was not activated.

Дополнительные сведения об обработке событий см. в разделе обработка и вызов событий.For more information about handling events, see Handling and Raising Events.

Применяется к

Дополнительно