Form.Activated Event


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Occurs when the form is activated in code or by the user.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public event EventHandler Activated


When the application is active and has multiple forms, the active form is the form with the input focus. A form that is not visible cannot be the active form. The simplest way to activate a visible form is to click it or use an appropriate keyboard combination.

To activate a form at run time using code, call the Activate method. 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.

For more information about handling events, see Handling and Raising Events.

The following code example demonstrates how to use the SetDesktopLocation, Closed, Load, Activated, and Activate members. 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;

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.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;

.NET Framework
Available since 1.1
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