Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms (in System.Windows.Forms.dll)
Visual Basic (Declaration)
Protected Overridable Sub OnLeave ( _
e As EventArgs _
)
Dim e As EventArgs
Me.OnLeave(e)
protected virtual void OnLeave(
EventArgs e
)
protected:
virtual void OnLeave(
EventArgs^ e
)
protected function OnLeave(
e : EventArgs
)
Raising an event invokes the event handler through a delegate. For more information, see Raising an Event.
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 Sub textBox1_Enter(sender As Object, e As System.EventArgs) Handles textBox1.Enter
' If the TextBox contains text, change its foreground and background colors.
If textBox1.Text <> [String].Empty Then
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)
End If
End Sub 'textBox1_Enter
Private Sub textBox1_Leave(sender As Object, e As System.EventArgs) Handles textBox1.Leave
' Reset the colors and selection of the TextBox after focus is lost.
textBox1.ForeColor = Color.Black
textBox1.BackColor = Color.White
textBox1.Select(0, 0)
End Sub 'textBox1_Leave
End Class 'Form1
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);
}
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);
}
}
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);
}
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
Reference