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Control.OnLeave Method

Raises the Leave event.

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

protected virtual void OnLeave(
	EventArgs e
)

Parameters

e
Type: System.EventArgs

An EventArgs that contains the event data.

Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.

The OnLeave method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding OnLeave in a derived class, be sure to call the base class's OnLeave method so that registered delegates receive the event.

The following code example uses the Leave event to reset a control to its former state.

private void textBox1_Enter(object sender, System.EventArgs e)
{
    // If the TextBox contains text, change its foreground and background colors. 
    if (textBox1.Text != String.Empty)
    {
        textBox1.ForeColor = Color.Red;
        textBox1.BackColor = Color.Black;
        // Move the selection pointer to the end of the text of the control.
        textBox1.Select(textBox1.Text.Length, 0);
    }
}

private void textBox1_Leave(object sender, System.EventArgs e)
{
    // Reset the colors and selection of the TextBox after focus is lost.
    textBox1.ForeColor = Color.Black;
    textBox1.BackColor = Color.White;
    textBox1.Select(0,0);
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
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