Form.Activated 事件

定義

發生於表單以程式碼或由使用者啟動時。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 

範例

下列範例示範如何使用 SetDesktopLocationClosedLoadActivatedActivate 成員。The following example demonstrates how to use the SetDesktopLocation, Closed, Load, Activated, and Activate members. 若要執行範例,請將下列程式碼貼入名為 Form1 的表單中,其中包含稱為 Button1Button,以及兩個名為 Label1Label2Label 控制項。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

備註

注意

當應用程式在作用中且有多個表單時,作用中的表單會是具有輸入焦點的表單。When the application is active and has multiple forms, the active form is the form with the input focus. 看不到的表單不能是現用表單。A form that is not visible cannot be the active form. 啟用可見表單最簡單的方式,就是按一下它,或使用適當的鍵盤組合。The simplest way to activate a visible form is to click it or use an appropriate keyboard combination.

若要在執行時間使用程式碼啟動表單,請呼叫 Activate 方法。To activate a form at run time using code, call the Activate method. 當表單未啟動時,您可以使用這個事件來執行工作,例如,根據表單資料的變更來更新表單的內容。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.

如需處理事件的詳細資訊,請參閱處理和引發事件For more information about handling events, see Handling and Raising Events.

適用於

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